Here is a patch that increases the max number of pptp sessions to 60.
http://cccweb.net/m0n0/generic-pc-1.3b4-60pptp.imgI'm running it on a p4 3.4 w/ 512mb of ram, so I figured my hardware could handle more than 16. Please don't ask me for any other images since I don't have that hardware and can't test.
Only two changes:
/etc/inc/globals.inc
"n_pptp_units" => 60,
"pptp_subnet" => 26,
This is an unsigned image since I did it with workon.sh.
*Use at your own risk!!!