VM:Secure does not have a way to automatically remove a user ID. But, with the Rules Facility, an expiration date/time for a user ID can be set so that after the specified date and time the user ID will no longer be able to logon.
For example, a contractor is going to work for 2 months. Create the user ID, then in the SYSTEM RULES file create a rule that states:
ACCEPT GEORGE LOGON EXPIRE 10/15/14.
Rules can be more specific. For instance, a rule could allow GEORGE to only logon on certain days and/or between certain hours.
For other RULES that can be used with expiration dates, review the VM:Secure Rules Facility Guide.