Contivity VPN on DSL suddenly is now failing after handsha..

Archived from groups: comp.dcom.vpn (More info?)

I have a laptop that uses Contivity VPN (v04_65.26) to connect from my
laptop at home to work, going through a DSL router (Linksys WRT54GS).
Up to a couple of days ago, everything was working fine. On Friday,
suddenly no connections of any kind through the router would work. We
could, however, directly connect to the DSL modem, login to our ISP,
and everything worked fine. So, we figured it was time to replace the
WRT54GS.

We replaced it last night with a WRT55AG. Now, most of the computers
in the house are working ok. However, although my laptop can get to
the internet through the browser, the VPN no longer works (I'm
hardwired through the router, not wireless). The symptom I see from
the VPN client is sort of odd, however. The normal process of VPN
login goes through a login dialog, a "Connecting..." dialog, then a
"Getting banner text" dialog, then a "Welcome ..." banner text dialog.
Normally, if there's something really wrong with my connection, the
"Connecting..." dialog fails, and it doesn't get to the "Getting banner
text" dialog. However, the current symptom is that it seems to finish
the "Connecting..." step, and it gets to the "Getting banner text"
dialog, but it always fails after a few seconds on that dialog. My
wife uses the vanilla VPN client in XP to get to her office network,
and that appears to be mostly working. It's only the Contivity VPN
from my laptop that is broken.

I spent several frustrating hours on hold with Earthlink (my DSL
provider), and some with Linksys, to no avail. The only thing Linksys
could recommend was to determine exactly which ports Contivity VPN was
using, and specify those ports in the "Port Triggering" section of the
router config.

Can anyone recommend any steps I can take to get more information to
help resolve this, or anything else that could help?