Index: oak-jcr/src/main/java/org/apache/jackrabbit/oak/jcr/SessionDelegate.java
===================================================================
--- oak-jcr/src/main/java/org/apache/jackrabbit/oak/jcr/SessionDelegate.java	(revision 1449711)
+++ oak-jcr/src/main/java/org/apache/jackrabbit/oak/jcr/SessionDelegate.java	(working copy)
@@ -290,7 +290,11 @@
      */
     @CheckForNull
     public String getOakPathOrNull(String jcrPath) {
-        return getNamePathMapper().getOakPath(jcrPath);
+        try {
+            return getNamePathMapper().getOakPath(jcrPath);
+        } catch (IllegalArgumentException ex) {
+            return null;
+        }
     }
 
     /**