Does anyone know of a way I can load test an installation of sqlexpress 2005 ?

I have a number of installs out there and am having issues with express. It seems to be getting stuck in the middle of a transaction and jamming up causing complete failure of my application.

Its an unusual problem.
The db only throws this problem up after a while. Its as if its building up crap

Any techniques or tools would be much appreciated.

Thanks All