Hello Gail, I know this post is old but what you mentioned relates directly to our issue. This isn't a major issue, just annoying. My customer has SQL 2005 SP4 Enterprise. As you said, the default .trc files total as 5 and rollover as designed. Back in August, for an unknown reason, two of the log files log_5194.trc and log_5195.trc stuck around and fell out of the 5 file cycle. So right now, we have the 5 default .trc files working as designed, but we have two extra .trc files from 22-Aug just sitting there. It won't let me delete because is says "file in use". I looked at sys.trace and it shows the only running trace as the current default trace file.
I'm guessing SQL service will have to be stopped in order to delete, but curious if you have any ideas. Thanks.