UBB.threads PHP Forum Software Community Forums Resources and Customizing Admin Zone Ukraine bad requests

FOLLOWUP: Basically they enter the url of my Forum ending with ubbthreads.php and then they add about 30 or 40 "+'s" to it.... eg. ubbthread.php++++++++++++++++++++
and some other characters...

Is this a known way to overflow the buffer or cache or ????

Thanks.