diff --git a/mozilla/content/base/public/nsIContent.h b/mozilla/content/base/public/nsIContent.h
index 90e22078967..66dea71af0f 100644
--- a/mozilla/content/base/public/nsIContent.h
+++ b/mozilla/content/base/public/nsIContent.h
@@ -195,6 +195,15 @@ public:
   NS_IMETHOD GetAttr(PRInt32 aNameSpaceID, nsIAtom* aName,
                      nsIAtom*& aPrefix, nsAWritableString& aResult) const = 0;
 
+  /**
+   * Determine if an attribute has been set.
+   *
+   * @param aNameSpaceId the namespace id of the attribute
+   * @param aAttr the attribute name
+   */
+
+  NS_IMETHOD_(PRBool) HasAttr(PRInt32 aNameSpaceID, nsIAtom* aName) const = 0;
+
   /**
    * Remove an attribute so that it is no longer explicitly specified.
    *
diff --git a/mozilla/content/base/src/nsCommentNode.cpp b/mozilla/content/base/src/nsCommentNode.cpp
index 045f0ce12a9..6499e42fb18 100644
--- a/mozilla/content/base/src/nsCommentNode.cpp
+++ b/mozilla/content/base/src/nsCommentNode.cpp
@@ -127,6 +127,9 @@ public:
                      nsAWritableString& aResult) const {
     return mInner.GetAttribute(aNameSpaceID, aAttribute, aResult);
   }
+  NS_IMETHOD_(PRBool) HasAttr(PRInt32 aNameSpaceID, nsIAtom* aAttribute) const {
+    return mInner.HasAttribute(aNameSpaceID, aAttribute);
+  }
   NS_IMETHOD GetAttr(PRInt32 aNameSpaceID, nsIAtom *aAttribute,
                      nsIAtom*& aPrefix, nsAWritableString& aResult) const {
     return mInner.GetAttribute(aNameSpaceID, aAttribute, aPrefix, aResult);
diff --git a/mozilla/content/base/src/nsGenericDOMDataNode.h b/mozilla/content/base/src/nsGenericDOMDataNode.h
index 76dff745265..447f04b00af 100644
--- a/mozilla/content/base/src/nsGenericDOMDataNode.h
+++ b/mozilla/content/base/src/nsGenericDOMDataNode.h
@@ -193,6 +193,9 @@ struct nsGenericDOMDataNode {
     aPrefix = nsnull;
     return NS_CONTENT_ATTR_NOT_THERE;
   }
+  PRBool HasAttribute(PRInt32 aNameSpaceID, nsIAtom *aAttribute) const {
+    return PR_FALSE;
+  }
   nsresult GetAttributeNameAt(PRInt32 aIndex, PRInt32& aNameSpaceID, 
                               nsIAtom*& aName, nsIAtom*& aPrefix) const {
     aNameSpaceID = kNameSpaceID_None;
@@ -516,6 +519,10 @@ struct nsGenericDOMDataNode {
                      nsIAtom*& aPrefix, nsAWritableString& aResult) const {    \
     return _g.GetAttribute(aNameSpaceID, aAttribute, aPrefix, aResult);    \
   }                                                                        \
+  NS_IMETHOD_(PRBool) HasAttr(PRInt32 aNameSpaceID, nsIAtom *aAttribute)   \
+                              const {                                      \
+    return _g.HasAttribute(aNameSpaceID, aAttribute);             \
+  }                                                                        \
   NS_IMETHOD SetAttr(PRInt32 aNameSpaceID, nsIAtom* aAttribute,            \
                      const nsAReadableString& aValue, PRBool aNotify) {    \
     return _g.SetAttribute(aNameSpaceID, aAttribute, aValue, aNotify);     \
diff --git a/mozilla/content/base/src/nsGenericElement.cpp b/mozilla/content/base/src/nsGenericElement.cpp
index 3a57ab33b21..dcaf472f113 100644
--- a/mozilla/content/base/src/nsGenericElement.cpp
+++ b/mozilla/content/base/src/nsGenericElement.cpp
@@ -1470,13 +1470,7 @@ nsGenericElement::HasAttribute(const nsAReadableString& aName, PRBool* aReturn)
   ni->GetNamespaceID(nsid);
   ni->GetNameAtom(*getter_AddRefs(nameAtom));
 
-  nsAutoString tmp;
-  nsresult rv = NS_STATIC_CAST(nsIContent *, this)->GetAttr(nsid,
-                                                            nameAtom,
-                                                            tmp);
-
-  *aReturn = rv == NS_CONTENT_ATTR_NOT_THERE ? PR_FALSE : PR_TRUE;
-
+  *aReturn = HasAttr(nsid, nameAtom);
   return NS_OK;
 }
 
@@ -1507,11 +1501,7 @@ nsGenericElement::HasAttributeNS(const nsAReadableString& aNamespaceURI,
     return NS_OK;
   }
 
-  nsAutoString tmp;
-  nsresult rv = NS_STATIC_CAST(nsIContent *, this)->GetAttr(nsid, name, tmp);
-
-  *aReturn = rv == NS_CONTENT_ATTR_NOT_THERE ? PR_FALSE : PR_TRUE;
-
+  *aReturn = HasAttr(nsid, name);
   return NS_OK;
 }
 
@@ -3358,6 +3348,29 @@ nsGenericContainerElement::GetAttr(PRInt32 aNameSpaceID, nsIAtom* aName,
   return rv;
 }
 
+NS_IMETHODIMP_(PRBool)
+nsGenericContainerElement::HasAttr(PRInt32 aNameSpaceID, nsIAtom* aName) const
+{
+  NS_ASSERTION(nsnull != aName, "must have attribute name");
+  if (nsnull == aName)
+    return PR_FALSE;
+  
+  if (nsnull != mAttributes) {
+    PRInt32 count = mAttributes->Count();
+    PRInt32 index;
+    for (index = 0; index < count; index++) {
+      const nsGenericAttribute* attr = (const nsGenericAttribute*)mAttributes->ElementAt(index);
+      if ((aNameSpaceID == kNameSpaceID_Unknown ||
+           attr->mNodeInfo->NamespaceEquals(aNameSpaceID)) &&
+          (attr->mNodeInfo->Equals(aName))) {
+        return PR_TRUE;
+      }
+    }
+  }
+
+  return PR_FALSE;
+}
+
 nsresult
 nsGenericContainerElement::UnsetAttr(PRInt32 aNameSpaceID,
                                      nsIAtom* aName, PRBool aNotify)
diff --git a/mozilla/content/base/src/nsGenericElement.h b/mozilla/content/base/src/nsGenericElement.h
index 4f6169386d0..c0a6e165553 100644
--- a/mozilla/content/base/src/nsGenericElement.h
+++ b/mozilla/content/base/src/nsGenericElement.h
@@ -485,6 +485,7 @@ public:
                      nsAWritableString& aResult) const;
   NS_IMETHOD GetAttr(PRInt32 aNameSpaceID, nsIAtom* aName,
                      nsIAtom*& aPrefix, nsAWritableString& aResult) const;
+  NS_IMETHOD_(PRBool) HasAttr(PRInt32 aNameSpaceID, nsIAtom* aName) const;
   NS_IMETHOD UnsetAttr(PRInt32 aNameSpaceID, nsIAtom* aAttribute,
                        PRBool aNotify);
   NS_IMETHOD GetAttrNameAt(PRInt32 aIndex,
diff --git a/mozilla/content/html/content/src/nsAttributeContent.cpp b/mozilla/content/html/content/src/nsAttributeContent.cpp
index 3c5c604740e..6699ccf7e06 100644
--- a/mozilla/content/html/content/src/nsAttributeContent.cpp
+++ b/mozilla/content/html/content/src/nsAttributeContent.cpp
@@ -146,6 +146,9 @@ public:
   NS_IMETHOD UnsetAttr(PRInt32 aNameSpaceID, nsIAtom* aAttribute, PRBool aNotify) { return NS_OK; }
   NS_IMETHOD GetAttr(PRInt32 aNameSpaceID, nsIAtom *aAttribute, nsAWritableString& aResult) const {return NS_CONTENT_ATTR_NOT_THERE; }
   NS_IMETHOD GetAttr(PRInt32 aNameSpaceID, nsIAtom *aAttribute, nsIAtom*& aPrefix, nsAWritableString& aResult) const {return NS_CONTENT_ATTR_NOT_THERE; }
+  NS_IMETHOD_(PRBool) HasAttr(PRInt32 aNameSpaceID, nsIAtom *aAttribute) const {
+    return PR_FALSE;
+  }
   NS_IMETHOD GetAttrNameAt(PRInt32 aIndex, PRInt32& aNameSpaceID, nsIAtom*& aName, nsIAtom*& aPrefix) const {
     aName = nsnull;
     aPrefix = nsnull;
diff --git a/mozilla/content/html/content/src/nsGenericHTMLElement.cpp b/mozilla/content/html/content/src/nsGenericHTMLElement.cpp
index 6a0c7e0846d..e43a13db23c 100644
--- a/mozilla/content/html/content/src/nsGenericHTMLElement.cpp
+++ b/mozilla/content/html/content/src/nsGenericHTMLElement.cpp
@@ -2055,6 +2055,12 @@ nsGenericHTMLElement::GetAttr(PRInt32 aNameSpaceID, nsIAtom *aAttribute,
   return result;
 }
 
+NS_IMETHODIMP_(PRBool)
+nsGenericHTMLElement::HasAttr(PRInt32 aNameSpaceID, nsIAtom* aName) const
+{
+  return mAttributes ? mAttributes->HasAttribute(aName) : PR_FALSE;
+}
+
 nsresult
 nsGenericHTMLElement::GetHTMLAttribute(nsIAtom* aAttribute,
                                        nsHTMLValue& aValue) const
diff --git a/mozilla/content/html/content/src/nsGenericHTMLElement.h b/mozilla/content/html/content/src/nsGenericHTMLElement.h
index 297f3aaae18..d0ec94f356b 100644
--- a/mozilla/content/html/content/src/nsGenericHTMLElement.h
+++ b/mozilla/content/html/content/src/nsGenericHTMLElement.h
@@ -161,6 +161,7 @@ public:
                      nsAWritableString& aResult) const;
   NS_IMETHOD GetAttr(PRInt32 aNameSpaceID, nsIAtom* aName,
                      nsIAtom*& aPrefix, nsAWritableString& aResult) const;
+  NS_IMETHOD_(PRBool) HasAttr(PRInt32 aNameSpaceID, nsIAtom* aName) const;
   NS_IMETHOD UnsetAttr(PRInt32 aNameSpaceID, nsIAtom* aName,
                        PRBool aNotify);
   NS_IMETHOD GetAttrNameAt(PRInt32 aIndex,
diff --git a/mozilla/content/html/style/src/nsHTMLAttributes.cpp b/mozilla/content/html/style/src/nsHTMLAttributes.cpp
index d0c4abd1e70..6bb0085358c 100644
--- a/mozilla/content/html/style/src/nsHTMLAttributes.cpp
+++ b/mozilla/content/html/style/src/nsHTMLAttributes.cpp
@@ -320,6 +320,7 @@ public:
                           nsHTMLValue& aValue) const;
   NS_IMETHOD GetAttribute(nsIAtom* aAttrName,
                           const nsHTMLValue** aValue) const;
+  NS_IMETHOD_(PRBool) HasAttribute(nsIAtom* aAttrName) const;
 
   NS_IMETHOD GetAttributeCount(PRInt32& aCount) const;
 
@@ -626,6 +627,16 @@ nsHTMLMappedAttributes::GetAttribute(nsIAtom* aAttrName,
   return NS_CONTENT_ATTR_NOT_THERE;
 }
 
+NS_IMETHODIMP_(PRBool)
+nsHTMLMappedAttributes::HasAttribute(nsIAtom* aAttrName) const
+{
+  if (!aAttrName)
+    return PR_FALSE;
+
+  const HTMLAttribute* attr = HTMLAttribute::FindHTMLAttribute(aAttrName, &mFirst);
+  return attr != nsnull;
+}
+
 NS_IMETHODIMP
 nsHTMLMappedAttributes::GetAttributeCount(PRInt32& aCount) const
 {
@@ -846,6 +857,8 @@ public:
   NS_IMETHOD GetAttribute(nsIAtom* aAttribute,
                           const nsHTMLValue** aValue) const;
 
+  NS_IMETHOD_(PRBool) HasAttribute(nsIAtom* aAttrName) const;
+
   NS_IMETHOD GetAttributeNameAt(PRInt32 aIndex,
                                 nsIAtom*& aName) const;
 
@@ -1358,6 +1371,18 @@ HTMLAttributesImpl::GetAttribute(nsIAtom* aAttrName,
   return result;
 }
 
+NS_IMETHODIMP_(PRBool)
+HTMLAttributesImpl::HasAttribute(nsIAtom* aAttrName) const
+{
+  if (mMapped)
+    return mMapped->HasAttribute(aAttrName);
+
+  const HTMLAttribute*  attr = HTMLAttribute::FindHTMLAttribute(aAttrName, mFirstUnmapped);
+  return attr != nsnull;
+}
+
+
+
 NS_IMETHODIMP
 HTMLAttributesImpl::GetAttributeNameAt(PRInt32 aIndex,
                                        nsIAtom*& aName) const
diff --git a/mozilla/content/html/style/src/nsIHTMLAttributes.h b/mozilla/content/html/style/src/nsIHTMLAttributes.h
index e8ef498fa8f..b1388d77ab8 100644
--- a/mozilla/content/html/style/src/nsIHTMLAttributes.h
+++ b/mozilla/content/html/style/src/nsIHTMLAttributes.h
@@ -81,6 +81,8 @@ public:
                           nsHTMLValue& aValue) const = 0;
   NS_IMETHOD GetAttribute(nsIAtom* aAttribute,
                           const nsHTMLValue** aValue) const = 0;
+  
+  NS_IMETHOD_(PRBool) HasAttribute(nsIAtom* aAttrName) const = 0;
 
   NS_IMETHOD GetAttributeNameAt(PRInt32 aIndex,
                                 nsIAtom*& aName) const = 0;
diff --git a/mozilla/content/xml/content/src/nsXMLProcessingInstruction.cpp b/mozilla/content/xml/content/src/nsXMLProcessingInstruction.cpp
index 416f768698d..a70d5a63e3a 100644
--- a/mozilla/content/xml/content/src/nsXMLProcessingInstruction.cpp
+++ b/mozilla/content/xml/content/src/nsXMLProcessingInstruction.cpp
@@ -222,6 +222,9 @@ public:
                      nsIAtom*& aPrefix, nsAWritableString& aResult) const {
     return mInner.GetAttribute(aNameSpaceID, aAttribute, aPrefix, aResult);
   }
+  NS_IMETHOD_(PRBool) HasAttr(PRInt32 aNameSpaceID, nsIAtom *aAttribute) const {
+    return mInner.HasAttribute(aNameSpaceID, aAttribute);
+  }
   NS_IMETHOD SetAttr(PRInt32 aNameSpaceID, nsIAtom* aAttribute,
                      const nsAReadableString& aValue, PRBool aNotify) {
     return mInner.SetAttribute(aNameSpaceID, aAttribute, aValue, aNotify);
diff --git a/mozilla/content/xul/content/src/nsXULElement.cpp b/mozilla/content/xul/content/src/nsXULElement.cpp
index 56e7342cfb3..76713351c41 100644
--- a/mozilla/content/xul/content/src/nsXULElement.cpp
+++ b/mozilla/content/xul/content/src/nsXULElement.cpp
@@ -1601,24 +1601,20 @@ nsXULElement::GetElementsByTagNameNS(const nsAReadableString& aNamespaceURI,
 NS_IMETHODIMP
 nsXULElement::HasAttribute(const nsAReadableString& aName, PRBool* aReturn)
 {
-    NS_ENSURE_ARG_POINTER(aReturn);
+  NS_ENSURE_ARG_POINTER(aReturn);
 
-    nsCOMPtr<nsIAtom> name;
-    nsCOMPtr<nsINodeInfo> ni;
-    PRInt32 nsid;
+  nsCOMPtr<nsIAtom> name;
+  nsCOMPtr<nsINodeInfo> ni;
+  PRInt32 nsid;
 
-    nsresult rv = NormalizeAttrString(aName, *getter_AddRefs(ni));
-    NS_ENSURE_SUCCESS(rv, rv);
+  nsresult rv = NormalizeAttrString(aName, *getter_AddRefs(ni));
+  NS_ENSURE_SUCCESS(rv, rv);
 
-    ni->GetNameAtom(*getter_AddRefs(name));
-    ni->GetNamespaceID(nsid);
+  ni->GetNameAtom(*getter_AddRefs(name));
+  ni->GetNamespaceID(nsid);
 
-    nsAutoString tmp;
-    rv = GetAttr(nsid, name, tmp);
-
-    *aReturn = rv == NS_CONTENT_ATTR_NOT_THERE ? PR_FALSE : PR_TRUE;
-
-    return NS_OK;
+  *aReturn = HasAttr(nsid, name);
+  return NS_OK;
 }
 
 NS_IMETHODIMP
@@ -1635,16 +1631,11 @@ nsXULElement::HasAttributeNS(const nsAReadableString& aNamespaceURI,
 
     if (nsid == kNameSpaceID_Unknown) {
         // Unkonwn namespace means no attr...
-
         *aReturn = PR_FALSE;
         return NS_OK;
     }
 
-    nsAutoString tmp;
-    nsresult rv = GetAttr(nsid, name, tmp);
-
-    *aReturn = rv == NS_CONTENT_ATTR_NOT_THERE ? PR_FALSE : PR_TRUE;
-
+    *aReturn = HasAttr(nsid, name);
     return NS_OK;
 }
 
@@ -2796,6 +2787,39 @@ nsXULElement::GetAttr(PRInt32 aNameSpaceID,
     return NS_CONTENT_ATTR_NOT_THERE;
 }
 
+NS_IMETHODIMP_(PRBool)
+nsXULElement::HasAttr(PRInt32 aNameSpaceID, nsIAtom* aName) const
+{
+  NS_ASSERTION(nsnull != aName, "must have attribute name");
+  if (!aName)
+    return PR_FALSE;
+
+  if (mSlots && mSlots->mAttributes) {
+    PRInt32 count = mSlots->mAttributes->Count();
+    for (PRInt32 i = 0; i < count; i++) {
+      nsXULAttribute* attr = NS_REINTERPRET_CAST(nsXULAttribute*,
+                                                 mSlots->mAttributes->ElementAt(i));
+
+      nsINodeInfo *ni = attr->GetNodeInfo();
+      if (ni->Equals(aName, aNameSpaceID))
+        return PR_TRUE;
+    }
+  }
+
+  if (mPrototype) {
+    PRInt32 count = mPrototype->mNumAttributes;
+    for (PRInt32 i = 0; i < count; i++) {
+      nsXULPrototypeAttribute* attr = &(mPrototype->mAttributes[i]);
+
+      nsINodeInfo *ni = attr->mNodeInfo;
+      if (ni->Equals(aName, aNameSpaceID))
+        return PR_TRUE;
+    }
+  }
+
+  return PR_FALSE;
+}
+
 NS_IMETHODIMP
 nsXULElement::UnsetAttr(PRInt32 aNameSpaceID,
                         nsIAtom* aName, PRBool aNotify)
diff --git a/mozilla/content/xul/content/src/nsXULElement.h b/mozilla/content/xul/content/src/nsXULElement.h
index 0c957782d3f..d4ebb64384b 100644
--- a/mozilla/content/xul/content/src/nsXULElement.h
+++ b/mozilla/content/xul/content/src/nsXULElement.h
@@ -410,6 +410,7 @@ public:
     NS_IMETHOD SetAttr(nsINodeInfo *aNodeInfo, const nsAReadableString& aValue, PRBool aNotify);
     NS_IMETHOD GetAttr(PRInt32 aNameSpaceID, nsIAtom* aName, nsAWritableString& aResult) const;
     NS_IMETHOD GetAttr(PRInt32 aNameSpaceID, nsIAtom* aName, nsIAtom*& aPrefix, nsAWritableString& aResult) const;
+    NS_IMETHOD_(PRBool) HasAttr(PRInt32 aNameSpaceID, nsIAtom* aName) const;
     NS_IMETHOD UnsetAttr(PRInt32 aNameSpaceID, nsIAtom* aName, PRBool aNotify);
     NS_IMETHOD GetAttrNameAt(PRInt32 aIndex, PRInt32& aNameSpaceID, 
                              nsIAtom*& aName, nsIAtom*& aPrefix) const;