What you are thinking of was the maximum amount of time that a Pre or Post command will be allowed to execute before BackupExec will force the termination of the pre/Post job
See http://seer.support.veritas.com/docs/270489.htm
http://seer.support.veritas.com/docs/192370.htm
If you know that a Pre/Post job should only take 1.5 minutes, you can alter the timeout to 2 or 3 minutes by following the TechNote