Remote Desktop and VPN issues, part II

Esteemed listers:

Back in September, I queried this group about getting Remote Desktop to
"work" on my home PC (WinXP Home SP2) to connect to my work PC (WinXP Pro
SP2) via Windows' VPN.  I can use my Win98SE box, which has no software
firewall, to do this, but I am stymied trying to do this with my WinXP Home
box.  (For a recap of that discussion, which had all the config details,
please see the thread starting with
http://archive.midrange.com/pctech/200509/msg00003.html.)

I never got it to work with a software firewall, and I'm back to needing a
solution.

The difference between then and now is that:
* I've completely ditched (uninstalled) the factory-installed Symantec crud.
* Switched from using Windows Firewall to Zone Alarm Internet Security
Suite.
* Along with ZA-ISS, I've "allowed" the Remote Desktop Application to run in
the "Trusted Zone", added TCP port 3389 to the "allowed" list, added the VPN
IP address and my work PC's IP address to the trusted zone.

As a test, I completely uninstalled ZA-ISS, rebooted, fired up VPN and
Remote Desktop, and I'm in.

I re-installed ZA-ISS, and back to the same old same old.

There's gotta be a way to make this work.  I'm sure I'm missing something in
the ZA config but danged if I can figure it out.

I am somewhat amazed at the apparent dearth of information for this on
ZoneLabs' support site.  Searching their site from Google, it's apparent
that they've dealt with this question numerous times in the past, but the
stuff Google turns up can only be accessed from Google's cache (as ZoneLabs
doesn't keep much history on their forums), and my search turns up the posts
which ask the question, but not the ones that answer them!  A non-site
specific search on Google turns up about a million or so hits; I gave up
after the first 50,000 or so.

Many, many TIA,
Dan