Webworks application halts at XHR on first time run after installation for Blackberry 6.0. However this doesn't happen on Blackberry OS 5.0. The user must close and re-launch application for the XHR to trigger successfully.
The same problem appear on OS 7.0 and 7.1. Because back button callback is also working as hxr it's not possible to use it on first application launch.