Integer parsing from show_submitted GET parameter (coming from user) does not account for strings which cannot be possibly parsed to an int. It popped up a while ago on our reviewboard instance. Apparently googlebots provide some weird parameters.

The link below produces the described problem:
http://demo.reviewboard.org/users/0xh3x/?show_submitted=sdfda

I've used the code shown in the diff on our instance. It prevents reviewboard to crank :)