Fatal error: Exception #1349094076

Hello,

When I leave a comment in a friend's wall, elgg gives me this fatal error, and says that: 

It has been found a fatal error while log in. Contact an administrator with the next information:

Exception #1349094076.

When I click "back" in the browser,  the comment is seeing, but always that a person want to comment some person's tablon, it appear this error. I'am log in (the community is private), and I'm using WISB cool theme, how can I fix this error? 

Thank you so much.