I am using Pentaho BI Suite community edition 3.0 stable version...

While logging out of my pentaho server (running in linux OS), i am getting an error page with strange lengthy HTML code, along with an alert box warning 'Error fetching XULOverlay List'. But this is not happening often and a rare scenario to reproduce.

When i google for this error, i got the following link,

But still don't know how to proceed further on this.

What are the possible causes for such errors? How to prevent it from happening?
As the application is in production environment i have to respond to it as early as possible, Can anyone help me on this ASAP?

Thanks a lot in advance,