[pptp-server] error 650 from behind linux masq box

[Bill Pitz]

I'm trying to configure pptp so I can connect my laptop to my home network
while I am at work.

At home, I have a Linux box running IP masquerading with several windows
PCs behind it. (I would like to be able to access files on these Windows
PCs remotely)

At work, we have a Linux firewall which runs IP Masquerading for all of
the workstations.  

When I try to connect from behind the linux firewall at work, I get error
650 on the windows machine.  The info in pptpd.log is as follows:
--
Jul 31 16:47:49 explosion pppd[4386]: pppd 2.3.7 started by root, uid 0
Jul 31 16:47:49 explosion pppd[4386]: Using interface ppp0
Jul 31 16:47:49 explosion pppd[4386]: Connect: ppp0 <--> /dev/pts/1
Jul 31 16:47:49 explosion pppd[4386]: sent [LCP ConfReq id=0x1 <asyncmap 0x0> <a
uth chap MD5> <magic 0x326b7dcc> <pcomp> <accomp>]
Jul 31 16:48:17 explosion last message repeated 9 times
Jul 31 16:48:20 explosion pppd[4386]: LCP: timeout sending Config-Requests
Jul 31 16:48:20 explosion pppd[4386]: Connection terminated.
Jul 31 16:48:20 explosion pppd[4386]: Connect time 0.6 minutes.
Jul 31 16:48:20 explosion pppd[4386]: Exit.
--

Any ideas as to what this could be?  I know that things are set up correctly
because I can connect fine if I place myself on the other side of the Linux
firewall and try to connect from a "real" IP address.  Is there anything you
know of that needs to be changed in the Masq config to get things working?
(Or will it work at all?)  I can see port 1723 through the firewall, fwiw.

Thanks in advance for any help you can provide...

-Bill