O.K weird one, the active Route processor seems to crash and switch over to the standby processor when ever i try to remove an non used ATM interface...?? anyone seen this behavour before, bcause seems like an IOS bug to me?
It is a bug, I talk to cisco guy a couple of days ago when I met the same situation, but cant open TAC since I am using pre release, just let you that's a known issue.
Please rate if helps. I will probably let you know when I get response if possible.