diff --git a/mozilla/content/xbl/src/nsXBLBinding.cpp b/mozilla/content/xbl/src/nsXBLBinding.cpp
index 3f9a45c2628..4caf8f80e27 100644
--- a/mozilla/content/xbl/src/nsXBLBinding.cpp
+++ b/mozilla/content/xbl/src/nsXBLBinding.cpp
@@ -206,6 +206,7 @@ XBLResolve(JSContext *cx, JSObject *obj, jsval id, uintN flags,
   // Now we either resolve or fail
   PRBool didInstall;
   nsresult rv = field->InstallField(context, origObj,
+                                    content->NodePrincipal(),
                                     protoBinding->DocURI(),
                                     &didInstall);
   if (NS_FAILED(rv)) {
diff --git a/mozilla/content/xbl/src/nsXBLProtoImplField.cpp b/mozilla/content/xbl/src/nsXBLProtoImplField.cpp
index 2adf6063b83..804b25e1239 100644
--- a/mozilla/content/xbl/src/nsXBLProtoImplField.cpp
+++ b/mozilla/content/xbl/src/nsXBLProtoImplField.cpp
@@ -94,6 +94,7 @@ nsXBLProtoImplField::AppendFieldText(const nsAString& aText)
 nsresult
 nsXBLProtoImplField::InstallField(nsIScriptContext* aContext,
                                   JSObject* aBoundNode,
+                                  nsIPrincipal* aPrincipal,
                                   nsIURI* aBindingDocURI,
                                   PRBool* aDidInstall) const
 {
@@ -124,14 +125,12 @@ nsXBLProtoImplField::InstallField(nsIScriptContext* aContext,
                "Shouldn't get here when an exception is pending!");
   
   // compile the literal string
-  // XXX Could we produce a better principal here?  Should be able
-  // to, really!
   PRBool undefined;
   nsCOMPtr<nsIScriptContext> context = aContext;
   rv = context->EvaluateStringWithValue(nsDependentString(mFieldText,
                                                           mFieldTextLength), 
                                         aBoundNode,
-                                        nsnull, uriSpec.get(),
+                                        aPrincipal, uriSpec.get(),
                                         mLineNumber, JSVERSION_LATEST,
                                         (void*) &result, &undefined);
   if (NS_FAILED(rv))
diff --git a/mozilla/content/xbl/src/nsXBLProtoImplField.h b/mozilla/content/xbl/src/nsXBLProtoImplField.h
index 420a48761a0..986356ee6eb 100644
--- a/mozilla/content/xbl/src/nsXBLProtoImplField.h
+++ b/mozilla/content/xbl/src/nsXBLProtoImplField.h
@@ -64,6 +64,7 @@ public:
 
   nsresult InstallField(nsIScriptContext* aContext,
                         JSObject* aBoundNode,
+                        nsIPrincipal* aPrincipal,
                         nsIURI* aBindingDocURI,
                         PRBool* aDidInstall) const;