Captive Portal block/allow access to other monowal service such as PPTP

From:	"Wesley K. Joyce" <wjoyce at uvi dot edu>
To:	<m0n0wall at lists dot m0n0 dot ch>, <m0n0wall dash dev at lists dot m0n0 dot ch>
Subject:	Captive Portal block/allow access to other monowal service such as PPTP
Date:	Sun, 19 Feb 2006 19:33:08 -0400

I want to use both the CP and PPTP server to control wirless users.  But it seems that a user can
make a PPTP connection without authenticating to the CP (which displays my AUP etc).  Is it possible
to reconfigure m0n0wall to block access to port 1723 (PPTP) until after the user authenticates to
the CP and all the while maintaning the same state information (ip/mac of user, idle time, hard
limit etc) it does for port 80?