Bug Tracking Wish List

Most likely this is available in some bug tracking systems, but I haven't seen it (used) in ours (TestTrack Pro), nor at other companies I've worked at. The concept is automatic escalation of bug priority over time, and it seems like it should be the default behavior to me. Think about it - if someone files a low priority bug, it still should get done eventually - it should not be endlessly bumped / kicked down the road for higher priority bugs. Over time, its priority should be raised automatically to the point where the system finally (in effect) says "It's been TWO YEARS FOR THIS ONE, ARE WE GOING TO FIX IT, OR WHAT?"