By default, all users can use PPTP. You can *disable* PPTP for a specific
user by setting the PPTPAccess property to "off" in that user's accounts
db entry:
/sbin/e-smith/db accounts setprop username PPTPAccess off
(replacing "username" with the user's username). To re-enable it,
just delete the property, or set it to "on":
/sbin/e-smith/db accounts delprop username PPTPAccess
(or /sbin/e-smith/db accounts setprop username PPTPAccess on)
Cheers,
--Rich