I have the same problem described in this post.
http://forums.contribs.org/index.php?topic=33728.0I running sme server 7.3.
I am having troubles trying to connect to my SME server on my office lan over my VPN connection from home. I am running SME 7 w/ no contribs on the server, XP Pro SP2 on the workstation. I created a new network connection for the PPTP session on the windows box. When I try to connect, it gets past the "Connecting to..." part, but errors out when it tries to authenticate the username/password. I am using strong encryption, and I am positive that I have typed the credentials properly. I also know that the boxes can see each other as I can ping the SME server and I can access it with SSH.
this is the log of vpn connection:
Apr 12 18:41:17 server pptpd[6554]: CTRL: Client **.**.**.** control connection started
Apr 12 18:41:17 server pptpd[6554]: CTRL: Starting call (launching pppd, opening GRE)
Apr 12 18:41:17 server pppd[6555]: Plugin radius.so loaded.
Apr 12 18:41:17 server pppd[6555]: RADIUS plugin initialized.
Apr 12 18:41:17 server pppd[6555]: pppd 2.4.4 started by root, uid 0
Apr 12 18:41:17 server kernel: divert: not allocating divert_blk for non-ethernet device ppp0
Apr 12 18:41:17 server pppd[6555]: Using interface ppp0
Apr 12 18:41:17 server pppd[6555]: Connect: ppp0 <--> /dev/pts/0
Apr 12 18:41:47 server pppd[6555]: LCP: timeout sending Config-Requests
Apr 12 18:41:50 server ntpd: logging to file /dev/stdout
Apr 12 18:41:54 server pppd[6555]: Modem hangup
Apr 12 18:41:54 server pptpd[6554]: CTRL: Reaping child PPP[6555]
Apr 12 18:41:54 server pppd[6555]: Connection terminated.
Apr 12 18:41:54 server kernel: divert: no divert_blk to free, ppp0 not ethernet
Apr 12 18:41:54 server pppd[6555]: Exit.
Apr 12 18:41:54 server pptpd[6554]: CTRL: Client **.**.**.** control connection finished
Thanks for help.