diff --git a/js/tamarin/MMgc/GC.h b/js/tamarin/MMgc/GC.h
index 1291eaaed752..e8ae3750087f 100644
--- a/js/tamarin/MMgc/GC.h
+++ b/js/tamarin/MMgc/GC.h
@@ -276,12 +276,12 @@ namespace MMgc
 		
 		void set(T obj) 
 		{
-			uintptr_t p = (uintptr_t)obj;
+			uintptr p = (uintptr)obj;
 			high = p >> HIDDENPTRSHIFT;
 			low = p & HIDDENPTRMASK;
 		}
-		uintptr_t high;
-		uintptr_t low;
+		uintptr high;
+		uintptr low;
 	};
 
 	/**
diff --git a/js/tamarin/core/E4XNode.cpp b/js/tamarin/core/E4XNode.cpp
index 3fbd34c9dc06..68220f32bafb 100644
--- a/js/tamarin/core/E4XNode.cpp
+++ b/js/tamarin/core/E4XNode.cpp
@@ -532,7 +532,8 @@ namespace avmplus
 				}
 				// !!@ Don't intern these namespaces since the intern table ignores
 				// the prefix value of the namespace.
-				this->_addInScopeNamespace (core, ns);
+				if (ns) // ns can be null if prefix is defined and attributeValue = ""
+					this->_addInScopeNamespace (core, ns);
 			}
 			else
 			{