[Zope] Access Rule no longer triggering

[Keith J. Farmer]

I have the following access rule in root:
Extract the part of HTTP_HOST we care about, and declare our rewrite
dictionary.

<dtml-let=20

  hostname=3D"_.string.lower(HTTP_HOST)"

  sitemap=3D"{ 'cloondara.thuban.org': 'cloondara',
             'cloondara.dyndns.org': 'cloondara',
             'www.thuban.org': 'thuban',
             'server.thuban.org': 'thuban',=20
             'leonov.dyndns.org': 'thuban'=20
           }"
>

<dtml-var hostname>
<br>
<dtml-var sitemap>

Do we have a match?=20
  <!--dtml-if expr=3D"sitemap.has_key(hostname)"-->

    Set the logical root: <dtml-let root=3D"'/'"><dtml-var root>
      <dtml-call "REQUEST.set('SiteRootPATH', '/')">
    </dtml-let>

    Add physical root: <dtml-let root=3D"thuban"><dtml-var root>
      <dtml-call "REQUEST['TraversalRequestNameStack'].append(root)">
    </dtml-let>

    Add vhost root: <dtml-let root=3D"'VHOSTS'"><dtml-var root>
      <dtml-call "REQUEST['TraversalRequestNameStack'].append(root)">=20
    </dtml-let>

  <!--/dtml-if-->
</dtml-let>
<br>
<dtml-var REQUEST>

In the VHOSTS/... folders I have SiteRoots with all blank attributes per
instructions.

When I had ZOPE running on port 8080, all was well, and the access rule
was performing admirably.  However, I've since moved zope to port 80,
and now it doesn't do anything.  Viewing the access rule from the editor
shows everything getting set properly.  I've attempted reinstallation
and reimporting the database, which didn't help. =20

I'm running this as an NT Service under Win2k Server.

Could someone explain what's going on?  Did I miss something in moving
Zope to port 80?