diff --git a/mozilla/content/xslt/public/nsIDocumentTransformer.h b/mozilla/content/xslt/public/nsIDocumentTransformer.h
index 20d6b743497..fd6646741dc 100644
--- a/mozilla/content/xslt/public/nsIDocumentTransformer.h
+++ b/mozilla/content/xslt/public/nsIDocumentTransformer.h
@@ -44,6 +44,7 @@ class nsIDOMDocument;
 class nsIDOMNode;
 class nsILoadGroup;
 class nsIURI;
+class nsIPrincipal;
 
 #define NS_ITRANSFORMOBSERVER_IID \
   {0xcce88481, 0x6eb3, 0x11d6, \
@@ -74,7 +75,7 @@ public:
 
   NS_IMETHOD SetTransformObserver(nsITransformObserver* aObserver) = 0;
   NS_IMETHOD LoadStyleSheet(nsIURI* aUri, nsILoadGroup* aLoadGroup,
-                            nsIURI* aReferrerUri) = 0;
+                            nsIPrincipal* aCallerPrincipal) = 0;
   NS_IMETHOD SetSourceContentModel(nsIDOMNode* aSource) = 0;
   NS_IMETHOD CancelLoads() = 0;
 };
diff --git a/mozilla/content/xslt/src/xslt/txMozillaStylesheetCompiler.cpp b/mozilla/content/xslt/src/xslt/txMozillaStylesheetCompiler.cpp
index cb7820fb92e..b714eee289a 100644
--- a/mozilla/content/xslt/src/xslt/txMozillaStylesheetCompiler.cpp
+++ b/mozilla/content/xslt/src/xslt/txMozillaStylesheetCompiler.cpp
@@ -55,6 +55,7 @@
 #include "nsIStreamConverterService.h"
 #include "nsISyncLoadDOMService.h"
 #include "nsIURI.h"
+#include "nsIPrincipal.h"
 #include "nsIWindowWatcher.h"
 #include "nsIXMLContentSink.h"
 #include "nsMimeTypes.h"
@@ -423,7 +424,7 @@ public:
     TX_DECL_ACOMPILEOBSERVER;
 
     nsresult startLoad(nsIURI* aUri, txStylesheetCompiler* aCompiler,
-                       nsIURI* aReferrerUri);
+                       nsIPrincipal* aCallerPrincipal);
 
 protected:
     nsAutoRefCnt mRefCnt;
@@ -492,19 +493,25 @@ txCompileObserver::onDoneCompiling(txStylesheetCompiler* aCompiler,
 
 nsresult
 txCompileObserver::startLoad(nsIURI* aUri, txStylesheetCompiler* aCompiler,
-                             nsIURI* aReferrerUri)
+                             nsIPrincipal* aCallerPrincipal)
 {
     nsresult rv;
-    if (aReferrerUri) {
+    nsCOMPtr<nsIURI> referrerURI;
+    
+    if (aCallerPrincipal) {
         nsCOMPtr<nsIScriptSecurityManager> securityManager = 
             do_GetService(NS_SCRIPTSECURITYMANAGER_CONTRACTID, &rv);
         NS_ENSURE_SUCCESS(rv, rv);
 
-        rv = securityManager->CheckLoadURI(aReferrerUri, aUri,
-                                           nsIScriptSecurityManager::STANDARD);
+        rv = securityManager->
+            CheckLoadURIWithPrincipal(aCallerPrincipal, aUri,
+                                      nsIScriptSecurityManager::STANDARD);
         NS_ENSURE_SUCCESS(rv, rv);
 
-        rv = securityManager->CheckSameOriginURI(aReferrerUri, aUri);
+        aCallerPrincipal->GetURI(getter_AddRefs(referrerURI));
+        NS_ASSERTION(referrerURI, "Caller principal must have a URI!");
+        
+        rv = securityManager->CheckSameOriginURI(referrerURI, aUri);
         NS_ENSURE_SUCCESS(rv, rv);
     }
 
@@ -520,8 +527,8 @@ txCompileObserver::startLoad(nsIURI* aUri, txStylesheetCompiler* aCompiler,
                                       NS_LITERAL_CSTRING("text/xml,application/xml,application/xhtml+xml,*/*;q=0.1"),
                                       PR_FALSE);
 
-        if (aReferrerUri) {
-            httpChannel->SetReferrer(aReferrerUri);
+        if (referrerURI) {
+            httpChannel->SetReferrer(referrerURI);
         }
     }
 
@@ -542,7 +549,7 @@ txCompileObserver::startLoad(nsIURI* aUri, txStylesheetCompiler* aCompiler,
 
 nsresult
 TX_LoadSheet(nsIURI* aUri, txMozillaXSLTProcessor* aProcessor,
-             nsILoadGroup* aLoadGroup, nsIURI* aReferrerUri)
+             nsILoadGroup* aLoadGroup, nsIPrincipal* aCallerPrincipal)
 {
     nsCAutoString uri;
     aUri->GetSpec(uri);
@@ -556,7 +563,7 @@ TX_LoadSheet(nsIURI* aUri, txMozillaXSLTProcessor* aProcessor,
         new txStylesheetCompiler(NS_ConvertUTF8toUCS2(uri), observer);
     NS_ENSURE_TRUE(compiler, NS_ERROR_OUT_OF_MEMORY);
 
-    return observer->startLoad(aUri, compiler, aReferrerUri);
+    return observer->startLoad(aUri, compiler, aCallerPrincipal);
 }
 
 /**
diff --git a/mozilla/content/xslt/src/xslt/txMozillaXSLTProcessor.cpp b/mozilla/content/xslt/src/xslt/txMozillaXSLTProcessor.cpp
index 2c416dda29d..f85e231af00 100644
--- a/mozilla/content/xslt/src/xslt/txMozillaXSLTProcessor.cpp
+++ b/mozilla/content/xslt/src/xslt/txMozillaXSLTProcessor.cpp
@@ -60,6 +60,7 @@
 #include "XMLUtils.h"
 #include "txUnknownHandler.h"
 #include "txXSLTProcessor.h"
+#include "nsIPrincipal.h"
 
 static NS_DEFINE_CID(kXMLDocumentCID, NS_XMLDOCUMENT_CID);
 
@@ -642,9 +643,9 @@ txMozillaXSLTProcessor::Reset()
 
 NS_IMETHODIMP
 txMozillaXSLTProcessor::LoadStyleSheet(nsIURI* aUri, nsILoadGroup* aLoadGroup,
-                                       nsIURI* aReferrerUri)
+                                       nsIPrincipal* aCallerPrincipal)
 {
-    nsresult rv = TX_LoadSheet(aUri, this, aLoadGroup, aReferrerUri);
+    nsresult rv = TX_LoadSheet(aUri, this, aLoadGroup, aCallerPrincipal);
     if (NS_FAILED(rv) && mObserver) {
         // This is most likely a network or security error, just
         // use the uri as context.
diff --git a/mozilla/content/xslt/src/xslt/txMozillaXSLTProcessor.h b/mozilla/content/xslt/src/xslt/txMozillaXSLTProcessor.h
index afd884b77d3..75727efb376 100644
--- a/mozilla/content/xslt/src/xslt/txMozillaXSLTProcessor.h
+++ b/mozilla/content/xslt/src/xslt/txMozillaXSLTProcessor.h
@@ -56,6 +56,7 @@
 class nsIURI;
 class nsIXMLContentSink;
 class nsIDOMNode;
+class nsIPrincipal;
 
 /* bacd8ad0-552f-11d3-a9f7-000064657374 */
 #define TRANSFORMIIX_XSLT_PROCESSOR_CID   \
@@ -138,7 +139,7 @@ public:
     // nsIDocumentTransformer interface
     NS_IMETHOD SetTransformObserver(nsITransformObserver* aObserver);
     NS_IMETHOD LoadStyleSheet(nsIURI* aUri, nsILoadGroup* aLoadGroup,
-                              nsIURI* aReferrerUri);
+                              nsIPrincipal* aCallerPrincipal);
     NS_IMETHOD SetSourceContentModel(nsIDOMNode* aSource);
     NS_IMETHOD CancelLoads() {return NS_OK;};
 
@@ -167,7 +168,8 @@ private:
 };
 
 extern nsresult TX_LoadSheet(nsIURI* aUri, txMozillaXSLTProcessor* aProcessor,
-                             nsILoadGroup* aLoadGroup, nsIURI* aReferrerUri);
+                             nsILoadGroup* aLoadGroup,
+                             nsIPrincipal* aCallerPrincipal);
 
 extern nsresult TX_CompileStylesheet(nsIDOMNode* aNode,
                                      txStylesheet** aStylesheet);