When the game catches an error, it will automaticly exit instead of just freezing, and prints you the error message.
If you’re not familiar with java, you won’t be able to solve the problem with that message as reference.
But we can help you.

In order to let us know that bug and try to fix it, click the  ”Send to bugtracker” button on the error-catcher.
This will send the all the information you see in the box to our server. We’ll instantly get an eMail that a new bug was submitted.
And we’ll instantly trying to fix it.

 A catched error

Thanks for your help.