Make Tickets due in Hours, not days

I posted this once and got no reply.

Is there any way to make Tickets due in HOURS instead of Days?

We have an emergency queue and run a cron job to escalate priority and send
the owner a reminder every hour. However, we need to be be able to set the
Due in hours to make this more effective.

Currently running RT3.0.7_01.

Joe Micciche