Sp_lock And Sp_who

Is there any way to write a line to a table showing who had a lock at a particular time?

We have a need to rollback transactions that persist for too long and cause application errors. what i want to do is to dump the details of the connection into a table for analysis later.

i am thinking along the lines of
SELECT loginname
FROM sp_who
WHERE spid in
(
SELECT spid
FROM sp_lock
)
or something!!!!

any ideas anyone?