Killing a thread

Hi Perl Thread GURUS,
	Here is my situation. I started, say 10 threads, executing some
command, 1 or 2 of them is hanging for over 2 hours. I want to put in
some logic that if the thread run time passes an hour threshold kill
that thread or return and fail the thread. Any ideas on how I can
accomplish this task? Thanks.

Sincerely yours,
Danny H. Wong