diff --git a/mozilla/content/base/src/nsDOMAttribute.cpp b/mozilla/content/base/src/nsDOMAttribute.cpp
index 4829cda18e7..81df09ea2ba 100644
--- a/mozilla/content/base/src/nsDOMAttribute.cpp
+++ b/mozilla/content/base/src/nsDOMAttribute.cpp
@@ -527,6 +527,16 @@ nsDOMAttribute::IsSupported(const nsAReadableString& aFeature,
   return nsGenericElement::InternalIsSupported(aFeature, aVersion, aReturn);
 }
 
+NS_IMETHODIMP
+nsDOMAttribute::GetBaseURI(nsAWritableString &aURI)
+{
+  aURI.Truncate();
+  nsresult rv = NS_OK;
+  nsCOMPtr<nsIDOMNode> node(do_QueryInterface(mContent));
+  if (node)
+    rv = node->GetBaseURI(aURI);
+  return rv;
+}
 
 //----------------------------------------------------------------------
 
diff --git a/mozilla/content/base/src/nsDocument.cpp b/mozilla/content/base/src/nsDocument.cpp
index ce3391ff9b1..9306a9f21dc 100644
--- a/mozilla/content/base/src/nsDocument.cpp
+++ b/mozilla/content/base/src/nsDocument.cpp
@@ -2738,6 +2738,20 @@ nsDocument::IsSupported(const nsAReadableString& aFeature,
   return nsGenericElement::InternalIsSupported(aFeature, aVersion, aReturn);
 }
 
+NS_IMETHODIMP
+nsDocument::GetBaseURI(nsAWritableString &aURI)
+{
+  aURI.Truncate();
+  if (mDocumentURL) {
+    nsXPIDLCString spec;
+    mDocumentURL->GetSpec(getter_Copies(spec));
+    if (spec) {
+      CopyASCIItoUCS2(nsLiteralCString(spec), aURI);
+    }
+  }
+  return NS_OK;
+}
+
 NS_IMETHODIMP    
 nsDocument::GetOwnerDocument(nsIDOMDocument** aOwnerDocument)
 {
diff --git a/mozilla/content/base/src/nsDocumentFragment.cpp b/mozilla/content/base/src/nsDocumentFragment.cpp
index 9ea14322382..239f5730948 100644
--- a/mozilla/content/base/src/nsDocumentFragment.cpp
+++ b/mozilla/content/base/src/nsDocumentFragment.cpp
@@ -101,6 +101,8 @@ public:
                             PRBool* aReturn)
   { return nsGenericContainerElement::IsSupported(aFeature, aVersion,
                                                   aReturn); }
+  NS_IMETHOD    GetBaseURI(nsAWritableString& aURI)
+  { return nsGenericContainerElement::GetBaseURI(aURI); }
 
   // interface nsIScriptObjectOwner
   NS_IMETHOD GetScriptObject(nsIScriptContext* aContext, void** aScriptObject);
diff --git a/mozilla/content/base/src/nsGenericDOMDataNode.cpp b/mozilla/content/base/src/nsGenericDOMDataNode.cpp
index 2e3c5b0d84c..31c1497224f 100644
--- a/mozilla/content/base/src/nsGenericDOMDataNode.cpp
+++ b/mozilla/content/base/src/nsGenericDOMDataNode.cpp
@@ -47,7 +47,6 @@
 #include "prprf.h"
 #include "nsCOMPtr.h"
 
-
 //----------------------------------------------------------------------
 
 nsGenericDOMDataNode::nsGenericDOMDataNode()
@@ -239,6 +238,25 @@ nsGenericDOMDataNode::IsSupported(const nsAReadableString& aFeature,
   return nsGenericElement::InternalIsSupported(aFeature, aVersion, aReturn);
 }
 
+nsresult
+nsGenericDOMDataNode::GetBaseURI(nsAWritableString& aURI)
+{
+  aURI.Truncate();
+  nsresult rv = NS_OK;
+  // DOM Data Node inherits the base from its parent element/document
+  nsCOMPtr<nsIDOMNode> node;
+  if (mParent) {
+    node = do_QueryInterface(mParent);
+  } else if (mDocument) {
+    node = do_QueryInterface(mDocument);
+  }
+
+  if (node)
+    rv = node->GetBaseURI(aURI);
+
+  return rv;
+}
+
 #if 0
 nsresult
 nsGenericDOMDataNode::Equals(nsIDOMNode* aNode, PRBool aDeep, PRBool* aReturn)
diff --git a/mozilla/content/base/src/nsGenericDOMDataNode.h b/mozilla/content/base/src/nsGenericDOMDataNode.h
index c30384e500f..2e1aebf11b7 100644
--- a/mozilla/content/base/src/nsGenericDOMDataNode.h
+++ b/mozilla/content/base/src/nsGenericDOMDataNode.h
@@ -124,6 +124,7 @@ struct nsGenericDOMDataNode {
   nsresult    IsSupported(const nsAReadableString& aFeature,
                           const nsAReadableString& aVersion,
                           PRBool* aReturn);
+  nsresult    GetBaseURI(nsAWritableString& aURI);
 
   // Implementation for nsIDOMCharacterData
   nsresult    GetData(nsAWritableString& aData);
@@ -353,6 +354,9 @@ struct nsGenericDOMDataNode {
                       PRBool* aReturn) {                                \
     return _g.IsSupported(aFeature, aVersion, aReturn);                 \
   }                                                                     \
+  NS_IMETHOD GetBaseURI(nsAWritableString& aURI) {                      \
+    return _g.GetBaseURI(aURI);                                         \
+  }                                                                     \
   NS_IMETHOD CloneNode(PRBool aDeep, nsIDOMNode** aReturn);
 
 #define NS_IMPL_IDOMCHARACTERDATA_USING_GENERIC_DOM_DATA(_g)                \
diff --git a/mozilla/content/base/src/nsGenericElement.cpp b/mozilla/content/base/src/nsGenericElement.cpp
index d92e94d7937..d7c620cdd4b 100644
--- a/mozilla/content/base/src/nsGenericElement.cpp
+++ b/mozilla/content/base/src/nsGenericElement.cpp
@@ -81,6 +81,9 @@
 
 #include "jsapi.h"
 
+// baseURI
+#include "nsIXMLDocument.h"
+
 //----------------------------------------------------------------------
 
 nsChildContentList::nsChildContentList(nsIContent *aContent)
@@ -696,6 +699,56 @@ nsGenericElement::HasAttributes(PRBool* aReturn)
   return NS_OK;
 }
 
+NS_IMETHODIMP
+nsGenericElement::GetXMLBaseURI(nsIURI **aURI)
+{
+  NS_ENSURE_ARG_POINTER(aURI);
+  aURI=nsnull;
+  return NS_OK;
+}
+
+
+NS_IMETHODIMP
+nsGenericElement::GetBaseURI(nsAWritableString& aURI)
+{
+  aURI.Truncate();
+  nsCOMPtr<nsIURI> uri;
+  nsCOMPtr<nsIXMLDocument> xmlDoc(do_QueryInterface(mDocument));
+  if (xmlDoc) {
+    // XML documents can use the XML Base (W3C spec) way of setting the base
+    // per element. We look at this node and its ancestors until we find
+    // the first XML content and get it's base.
+    nsCOMPtr<nsIContent> content(do_QueryInterface(NS_STATIC_CAST(nsIContent*,this)));
+    while (content) {
+      nsCOMPtr<nsIXMLContent> xmlContent(do_QueryInterface(content));
+      if (xmlContent) {
+        xmlContent->GetXMLBaseURI(getter_AddRefs(uri));
+        break;
+      }
+      nsCOMPtr<nsIContent> tmp(content);
+      tmp->GetParent(*getter_AddRefs(content));
+    }
+  }
+
+  if (!uri && mDocument) {
+    // HTML document or for some reason there was no XML content in XML document
+    mDocument->GetBaseURL(*getter_AddRefs(uri));
+    if (!uri) {
+      uri = dont_AddRef(mDocument->GetDocumentURL());
+    }
+  }
+
+  if (uri) {
+    nsXPIDLCString spec;
+    uri->GetSpec(getter_Copies(spec));
+    if (spec) {
+      CopyASCIItoUCS2(nsLiteralCString(spec), aURI);
+    }
+  }
+  
+  return NS_OK;
+}
+
 NS_IMETHODIMP
 nsGenericElement::GetAttributes(nsIDOMNamedNodeMap** aAttributes)
 {
diff --git a/mozilla/content/base/src/nsGenericElement.h b/mozilla/content/base/src/nsGenericElement.h
index 6b67ac19f24..8dac32d4a0d 100644
--- a/mozilla/content/base/src/nsGenericElement.h
+++ b/mozilla/content/base/src/nsGenericElement.h
@@ -210,6 +210,7 @@ public:
   NS_IMETHOD SetContainingNameSpace(nsINameSpace* aNameSpace);
   NS_IMETHOD GetContainingNameSpace(nsINameSpace*& aNameSpace) const;
   NS_IMETHOD MaybeTriggerAutoLink(nsIWebShell *aShell);
+  NS_IMETHOD GetXMLBaseURI(nsIURI **aURI);
 
   // nsIHTMLContent interface methods
   NS_IMETHOD Compact();
@@ -268,6 +269,7 @@ public:
   NS_IMETHOD IsSupported(const nsAReadableString& aFeature,
                          const nsAReadableString& aVersion, PRBool* aReturn);
   NS_IMETHOD HasAttributes(PRBool* aHasAttributes);
+  NS_IMETHOD GetBaseURI(nsAWritableString& aURI);
 
   // nsIDOMElement method implementation
   NS_IMETHOD GetTagName(nsAWritableString& aTagName);
@@ -471,5 +473,6 @@ protected:
   NS_IMETHOD    Normalize() { return _to Normalize(); }  \
   NS_IMETHOD    IsSupported(const nsAReadableString& aFeature, const nsAReadableString& aVersion, PRBool* aReturn) { return _to IsSupported(aFeature, aVersion, aReturn); }  \
   NS_IMETHOD    HasAttributes(PRBool* aReturn) { return _to HasAttributes(aReturn); }  \
+  NS_IMETHOD    GetBaseURI(nsAWritableString& aURI) { return _to GetBaseURI(aURI); }  \
 
 #endif /* nsGenericElement_h___ */
diff --git a/mozilla/content/html/document/src/nsHTMLDocument.cpp b/mozilla/content/html/document/src/nsHTMLDocument.cpp
index 81842d16645..b98c892013d 100644
--- a/mozilla/content/html/document/src/nsHTMLDocument.cpp
+++ b/mozilla/content/html/document/src/nsHTMLDocument.cpp
@@ -1705,6 +1705,21 @@ nsHTMLDocument::IsSupported(const nsAReadableString& aFeature,
   return nsDocument::IsSupported(aFeature, aVersion, aReturn);
 }
 
+NS_IMETHODIMP
+nsHTMLDocument::GetBaseURI(nsAWritableString &aURI)
+{
+  aURI.Truncate();
+  nsCOMPtr<nsIURI> uri(do_QueryInterface(mBaseURL ? mBaseURL : mDocumentURL));
+  if (uri) {
+    nsXPIDLCString spec;
+    uri->GetSpec(getter_Copies(spec));
+    if (spec) {
+      CopyASCIItoUCS2(nsLiteralCString(spec), aURI);
+    }
+  }
+  return NS_OK;
+}
+
 
 //
 // nsIDOMHTMLDocument interface implementation
diff --git a/mozilla/content/xml/content/public/nsIXMLContent.h b/mozilla/content/xml/content/public/nsIXMLContent.h
index b087efcdebe..5691fd44410 100644
--- a/mozilla/content/xml/content/public/nsIXMLContent.h
+++ b/mozilla/content/xml/content/public/nsIXMLContent.h
@@ -30,6 +30,7 @@
 class nsINameSpace;
 class nsINodeInfo;
 class nsIWebShell;
+class nsIURI;
 
 #define NS_IXMLCONTENT_IID \
  { 0xa6cf90cb, 0x15b3, 0x11d2, \
@@ -55,6 +56,8 @@ public:
    * links, so processing should usually stop after that as well.
    */
   NS_IMETHOD MaybeTriggerAutoLink(nsIWebShell *aShell) = 0;
+
+  NS_IMETHOD GetXMLBaseURI(nsIURI **aURI) = 0;
 };
 
 // Some return values for MaybeTriggerAutoLink
diff --git a/mozilla/content/xml/content/src/nsXMLElement.cpp b/mozilla/content/xml/content/src/nsXMLElement.cpp
index 929688c119d..3b0e398ab62 100644
--- a/mozilla/content/xml/content/src/nsXMLElement.cpp
+++ b/mozilla/content/xml/content/src/nsXMLElement.cpp
@@ -162,19 +162,16 @@ static inline nsresult MakeURI(const char *aSpec, nsIURI *aBase, nsIURI **aURI)
   return service->NewURI(aSpec,aBase,aURI);
 }
 
-nsresult 
+NS_IMETHODIMP
 nsXMLElement::GetXMLBaseURI(nsIURI **aURI)
 {
-  NS_ABORT_IF_FALSE(aURI,"null ptr");
-  if (!aURI)
-    return NS_ERROR_NULL_POINTER;
-
+  NS_ENSURE_ARG_POINTER(aURI);
   *aURI = nsnull;
   
   nsresult rv;
 
   nsAutoString base;
-  nsCOMPtr<nsIContent> content = do_QueryInterface(NS_STATIC_CAST(nsIXMLContent*,this),&rv);
+  nsCOMPtr<nsIContent> content(do_QueryInterface(NS_STATIC_CAST(nsIXMLContent*,this),&rv));
   while (NS_SUCCEEDED(rv) && content) {
     nsAutoString value;
     rv = content->GetAttribute(kNameSpaceID_XML,kBaseAtom,value);
@@ -228,7 +225,11 @@ nsXMLElement::GetXMLBaseURI(nsIURI **aURI)
 
   if (NS_SUCCEEDED(rv)) {
     if (!*aURI && mDocument) {
-      nsCOMPtr<nsIURI> docBase = dont_AddRef(mDocument->GetDocumentURL());
+      nsCOMPtr<nsIURI> docBase;
+      mDocument->GetBaseURL(*getter_AddRefs(docBase));
+      if (!docBase) {
+        docBase = dont_AddRef(mDocument->GetDocumentURL());
+      }
       if (base.IsEmpty()) {
         *aURI = docBase.get();    
         NS_IF_ADDREF(*aURI);  // nsCOMPtr releases this once
diff --git a/mozilla/content/xml/content/src/nsXMLElement.h b/mozilla/content/xml/content/src/nsXMLElement.h
index fc1853d02b9..abefdc83106 100644
--- a/mozilla/content/xml/content/src/nsXMLElement.h
+++ b/mozilla/content/xml/content/src/nsXMLElement.h
@@ -61,6 +61,7 @@ public:
   NS_IMETHOD SetContainingNameSpace(nsINameSpace* aNameSpace);
   NS_IMETHOD GetContainingNameSpace(nsINameSpace*& aNameSpace) const;
   NS_IMETHOD MaybeTriggerAutoLink(nsIWebShell *aShell);
+  NS_IMETHOD GetXMLBaseURI(nsIURI **aURI);
 
   // nsIStyledContent
   NS_IMETHOD GetID(nsIAtom*& aResult) const;
@@ -77,7 +78,6 @@ public:
   NS_IMETHOD SizeOf(nsISizeOfHandler* aSizer, PRUint32* aResult) const;
 
 protected:
-  nsresult GetXMLBaseURI(nsIURI **aURI);  // XXX This should perhaps be moved to nsIXMLContent
   PRBool mIsLink;
   nsINameSpace* mNameSpace;
 };
diff --git a/mozilla/content/xul/content/src/nsXULAttributes.cpp b/mozilla/content/xul/content/src/nsXULAttributes.cpp
index 6adef5ea4ef..b5bf5e02d43 100644
--- a/mozilla/content/xul/content/src/nsXULAttributes.cpp
+++ b/mozilla/content/xul/content/src/nsXULAttributes.cpp
@@ -462,6 +462,12 @@ nsXULAttribute::IsSupported(const nsAReadableString& aFeature,
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
+NS_IMETHODIMP
+nsXULAttribute::GetBaseURI(nsAWritableString &aURI)
+{
+  NS_NOTYETIMPLEMENTED("write me");
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
 
 // nsIDOMAttr interface
 
diff --git a/mozilla/content/xul/content/src/nsXULElement.cpp b/mozilla/content/xul/content/src/nsXULElement.cpp
index 59d11a2a446..f2ef5a38b5a 100644
--- a/mozilla/content/xul/content/src/nsXULElement.cpp
+++ b/mozilla/content/xul/content/src/nsXULElement.cpp
@@ -1791,6 +1791,36 @@ nsXULElement::MaybeTriggerAutoLink(nsIWebShell *aShell)
   return NS_OK;
 }
 
+NS_IMETHODIMP
+nsXULElement::GetXMLBaseURI(nsIURI **aURI)
+{
+  // XXX TODO, should share the impl with nsXMLElement
+  NS_ENSURE_ARG_POINTER(aURI);
+  *aURI=nsnull;
+  if (mDocument) {
+    mDocument->GetBaseURL(*aURI);
+    if (!*aURI) {
+      *aURI = mDocument->GetDocumentURL();
+    }
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsXULElement::GetBaseURI(nsAWritableString &aURI)
+{
+  // XXX TODO, should share the impl with nsXMLElement
+  aURI.Truncate();
+  nsresult rv = NS_OK;
+  if (mDocument) {
+    nsCOMPtr<nsIDOMDocument> doc(do_QueryInterface(mDocument));
+    if (doc) {
+      rv = doc->GetBaseURI(aURI);
+    }
+  }
+  return rv;
+}
+
 
 //----------------------------------------------------------------------
 // nsIXULContent interface
diff --git a/mozilla/content/xul/content/src/nsXULElement.h b/mozilla/content/xul/content/src/nsXULElement.h
index 69e27d085c1..6a5d2fda060 100644
--- a/mozilla/content/xul/content/src/nsXULElement.h
+++ b/mozilla/content/xul/content/src/nsXULElement.h
@@ -388,6 +388,7 @@ public:
     NS_IMETHOD SetContainingNameSpace(nsINameSpace* aNameSpace);
     NS_IMETHOD GetContainingNameSpace(nsINameSpace*& aNameSpace) const;
     NS_IMETHOD MaybeTriggerAutoLink(nsIWebShell *aShell);
+    NS_IMETHOD GetXMLBaseURI(nsIURI **aURI);
 
     // nsIStyledContent
     NS_IMETHOD GetID(nsIAtom*& aResult) const;
diff --git a/mozilla/content/xul/document/src/nsXULDocument.cpp b/mozilla/content/xul/document/src/nsXULDocument.cpp
index ae2e2523447..463f19f2e94 100644
--- a/mozilla/content/xul/document/src/nsXULDocument.cpp
+++ b/mozilla/content/xul/document/src/nsXULDocument.cpp
@@ -3487,6 +3487,20 @@ nsXULDocument::IsSupported(const nsAReadableString& aFeature,
   return NS_ERROR_NOT_IMPLEMENTED;
 }
 
+NS_IMETHODIMP
+nsXULDocument::GetBaseURI(nsAWritableString &aURI)
+{
+  aURI.Truncate();
+  if (mDocumentURL) {
+    nsXPIDLCString spec;
+    mDocumentURL->GetSpec(getter_Copies(spec)); // XUL documents do not have base URL?
+    if (spec) {
+      CopyASCIItoUCS2(nsLiteralCString(spec), aURI);
+    }
+  }
+  return NS_OK;
+}
+
 
 //----------------------------------------------------------------------
 //
diff --git a/mozilla/dom/public/coreDom/nsIDOMNSDocument.h b/mozilla/dom/public/coreDom/nsIDOMNSDocument.h
index 30edc745f88..2d3af063820 100644
--- a/mozilla/dom/public/coreDom/nsIDOMNSDocument.h
+++ b/mozilla/dom/public/coreDom/nsIDOMNSDocument.h
@@ -78,8 +78,8 @@ public:
 
 #define NS_FORWARD_IDOMNSDOCUMENT(_to)  \
   NS_IMETHOD    GetCharacterSet(nsAWritableString& aCharacterSet) { return _to GetCharacterSet(aCharacterSet); } \
-  NS_IMETHOD    GetDir(nsAWritableString& aDir);  \
-  NS_IMETHOD    SetDir(const nsAReadableString& aDir);  \
+  NS_IMETHOD    GetDir(nsAWritableString& aDir) { return _to GetDir(aDir); } \
+  NS_IMETHOD    SetDir(const nsAReadableString& aDir) { return _to SetDir(aDir); } \
   NS_IMETHOD    GetPlugins(nsIDOMPluginArray** aPlugins) { return _to GetPlugins(aPlugins); } \
   NS_IMETHOD    GetLocation(jsval* aLocation) { return _to GetLocation(aLocation); } \
   NS_IMETHOD    SetLocation(jsval aLocation) { return _to SetLocation(aLocation); } \
diff --git a/mozilla/dom/public/coreDom/nsIDOMNode.h b/mozilla/dom/public/coreDom/nsIDOMNode.h
index bb4ada22caf..47b704b059c 100644
--- a/mozilla/dom/public/coreDom/nsIDOMNode.h
+++ b/mozilla/dom/public/coreDom/nsIDOMNode.h
@@ -85,6 +85,8 @@ public:
 
   NS_IMETHOD    GetLocalName(nsAWritableString& aLocalName)=0;
 
+  NS_IMETHOD    GetBaseURI(nsAWritableString& aBaseURI)=0;
+
   NS_IMETHOD    InsertBefore(nsIDOMNode* aNewChild, nsIDOMNode* aRefChild, nsIDOMNode** aReturn)=0;
 
   NS_IMETHOD    ReplaceChild(nsIDOMNode* aNewChild, nsIDOMNode* aOldChild, nsIDOMNode** aReturn)=0;
@@ -122,6 +124,7 @@ public:
   NS_IMETHOD    GetPrefix(nsAWritableString& aPrefix);  \
   NS_IMETHOD    SetPrefix(const nsAReadableString& aPrefix);  \
   NS_IMETHOD    GetLocalName(nsAWritableString& aLocalName);  \
+  NS_IMETHOD    GetBaseURI(nsAWritableString& aBaseURI);  \
   NS_IMETHOD    InsertBefore(nsIDOMNode* aNewChild, nsIDOMNode* aRefChild, nsIDOMNode** aReturn);  \
   NS_IMETHOD    ReplaceChild(nsIDOMNode* aNewChild, nsIDOMNode* aOldChild, nsIDOMNode** aReturn);  \
   NS_IMETHOD    RemoveChild(nsIDOMNode* aOldChild, nsIDOMNode** aReturn);  \
@@ -151,6 +154,7 @@ public:
   NS_IMETHOD    GetPrefix(nsAWritableString& aPrefix) { return _to GetPrefix(aPrefix); } \
   NS_IMETHOD    SetPrefix(const nsAReadableString& aPrefix) { return _to SetPrefix(aPrefix); } \
   NS_IMETHOD    GetLocalName(nsAWritableString& aLocalName) { return _to GetLocalName(aLocalName); } \
+  NS_IMETHOD    GetBaseURI(nsAWritableString& aBaseURI) { return _to GetBaseURI(aBaseURI); } \
   NS_IMETHOD    InsertBefore(nsIDOMNode* aNewChild, nsIDOMNode* aRefChild, nsIDOMNode** aReturn) { return _to InsertBefore(aNewChild, aRefChild, aReturn); }  \
   NS_IMETHOD    ReplaceChild(nsIDOMNode* aNewChild, nsIDOMNode* aOldChild, nsIDOMNode** aReturn) { return _to ReplaceChild(aNewChild, aOldChild, aReturn); }  \
   NS_IMETHOD    RemoveChild(nsIDOMNode* aOldChild, nsIDOMNode** aReturn) { return _to RemoveChild(aOldChild, aReturn); }  \
diff --git a/mozilla/dom/public/idl/coreDom/Node.idl b/mozilla/dom/public/idl/coreDom/Node.idl
index b8121bbf20f..e9eb4fbe37b 100644
--- a/mozilla/dom/public/idl/coreDom/Node.idl
+++ b/mozilla/dom/public/idl/coreDom/Node.idl
@@ -56,6 +56,9 @@ interface Node {
    readonly attribute DOMString        localName;
    // Introduced in DOM Level 2:
    boolean            hasAttributes();
+
+   // Introduced in DOM Level 3:
+   readonly attribute DOMString        baseURI;
 };
 
  interface EventTarget {
diff --git a/mozilla/dom/public/nsDOMPropEnums.h b/mozilla/dom/public/nsDOMPropEnums.h
index 79760fcb0ff..108c7b5f027 100644
--- a/mozilla/dom/public/nsDOMPropEnums.h
+++ b/mozilla/dom/public/nsDOMPropEnums.h
@@ -741,6 +741,7 @@ enum nsDOMProp {
     NS_DOM_PROP_NAVIGATOR_VENDORSUB,
     NS_DOM_PROP_NODE_APPENDCHILD, 
     NS_DOM_PROP_NODE_ATTRIBUTES, 
+    NS_DOM_PROP_NODE_BASEURI, 
     NS_DOM_PROP_NODE_CHILDNODES, 
     NS_DOM_PROP_NODE_CLONENODE, 
     NS_DOM_PROP_NODE_FIRSTCHILD, 
diff --git a/mozilla/dom/public/nsDOMPropNames.h b/mozilla/dom/public/nsDOMPropNames.h
index 3e7a8fb3ad2..c36e3ff6c0d 100644
--- a/mozilla/dom/public/nsDOMPropNames.h
+++ b/mozilla/dom/public/nsDOMPropNames.h
@@ -739,6 +739,7 @@
     "navigator.vendorsub", \
     "node.appendchild", \
     "node.attributes", \
+    "node.baseuri", \
     "node.childnodes", \
     "node.clonenode", \
     "node.firstchild", \
diff --git a/mozilla/dom/src/coreDOM/nsJSNode.cpp b/mozilla/dom/src/coreDOM/nsJSNode.cpp
index d0ff576ef2e..ebfb6f8fe0d 100644
--- a/mozilla/dom/src/coreDOM/nsJSNode.cpp
+++ b/mozilla/dom/src/coreDOM/nsJSNode.cpp
@@ -71,7 +71,8 @@ enum Node_slots {
   NODE_OWNERDOCUMENT = -11,
   NODE_NAMESPACEURI = -12,
   NODE_PREFIX = -13,
-  NODE_LOCALNAME = -14
+  NODE_LOCALNAME = -14,
+  NODE_BASEURI = -15
 };
 
 /***********************************************************************/
@@ -270,6 +271,18 @@ GetNodeProperty(JSContext *cx, JSObject *obj, jsval id, jsval *vp)
         }
         break;
       }
+      case NODE_BASEURI:
+      {
+        rv = secMan->CheckScriptAccess(cx, obj, NS_DOM_PROP_NODE_BASEURI, PR_FALSE);
+        if (NS_SUCCEEDED(rv)) {
+          nsAutoString prop;
+          rv = a->GetBaseURI(prop);
+          if (NS_SUCCEEDED(rv)) {
+            nsJSUtils::nsConvertStringToJSVal(prop, cx, vp);
+          }
+        }
+        break;
+      }
       default:
         return nsJSUtils::nsCallJSScriptObjectGetProperty(a, cx, obj, id, vp);
     }
@@ -360,6 +373,7 @@ static JSPropertySpec NodeProperties[] =
   {"namespaceURI",    NODE_NAMESPACEURI,    JSPROP_ENUMERATE | JSPROP_READONLY},
   {"prefix",    NODE_PREFIX,    JSPROP_ENUMERATE},
   {"localName",    NODE_LOCALNAME,    JSPROP_ENUMERATE | JSPROP_READONLY},
+  {"baseURI",    NODE_BASEURI,    JSPROP_ENUMERATE | JSPROP_READONLY},
   {0}
 };