Session Mgmt in MySQL - cleanup

I've adapted a session management script I found on www.phpbuilder.com for storing session info in MySQL, but I'm wondering about "garbage collection". Does the system do the garbage collection itself somehow, or should my sess_open function call sess_gc directly? I noticed that when I invoke session_destroy(), the session row for that id remains in the database - but the session data associated with that session id is gone. Is that normal? I almost expected the whole session row to be removed, especially since the sess_destroy function does actually does a DELETE FROM. I don't quite understand how this is working. Is there some documentation somewhere on the "user"(database) functions for a session management in a database, like what each function is expecting, and what each should return, and when each one is called??? TIA. -- Hardy Merrill Mission Critical Linux, Inc. http://www.missioncriticallinux.com