Is there a way to have the server terminate a long running
transaction?

I have a multi-threaded, multi-tier application with a FB 1.5.3 DB.
Every once in a while a thread fails / leaks and I would like to find a
way to kill the transaction within the thread. Since my application is
losing it's handle to the thread I am hoping there is a setting on the
server that can help me here.

I am wanting to move to FB 2.0. My previous attempt to move to 2.0
failed due to the garbage collector getting in the way waiting on
these "lost" threads to complete their transaction.