share lock error

I am getting this in my log file:
2006-10-05 16:06:23 [6469] ERROR:  deadlock detected
DETAIL:  Process 6469 waits for ShareLock on transaction 668582701;
blocked by process 28763.
        Process 28763 waits for ShareLock on transaction 668586325;
blocked by process 6469.

I believe the scenario is likely like:
user 1 does something which causes a lock on element a
user 2 does something which causes a lock on element b
user 1 tries to do something and blocks waiting for a lock on b
user 2 tries to do something and blocks waiting for a lock on a
deadlock

I believe that the elements "a" and "b" are different tables.

The solution is to have both apps lock "a" first, then "b", hence no
deadlock could occur.  Problem is, I don't know what the underlying
entities are.

Is there somewhere I can gather more information about which tables or
entities are behind the transaction number?

Thanks in advance


--
Terry Fielder
terry@greatgulfhomes.com
Associate Director Software Development and Deployment
Great Gulf Homes / Ashton Woods Homes
Fax: (416) 441-9085