[Zope] Netscape 4, cookies and domains

We're using ZEO to feed two Zope clients and we're using Sessions with a packless storage to keep track of session info. It works great except for one problem related to Netscape 4 that I've seen referenced before in other contexts. I've got browseridmanager set to feed cookies with a domain of .mydomain.com. So www1.mydomain.com and www2.mydomain.com and www.mydomain.com all work fine. But mydomain.com doesn't get a browser ID set. If I take off the domain setting in the browser ID manager, it works with Netscape 4 with mydomain.com but of course doesn't work on any of the other domains and doesn't share domain info across the board. Is there any workaround for this short of forcing them to a www.mydomain.com URL? Thanks! - Chris