You'd need to script any change from inactive to closed to deleted if you want to do that in any automatic fashion, after making an account closed you could run a cron job that deleted closed account but you'd obviously need to be sure it's really due to be deleted.
You'll want the following for closing the account:
Code:
modifyAccount(ma) {name@domain|id} [attr1 value1 [attr2 value2...]
zmprov ma name@domain zimbraAccountStatus closed The ldap directory schame is here:
5.0.15 Directory Schema - Zimbra :: Wiki and in the Zimbra directory for the current version of openLDAP as zimbra.schema