[Zope] Problem with VirtualHostMonster

Hi, I was using Zope "SiteRoot" product until now (without any problem) to handle my Zope virtual hosting behind an Apache server with rewrite rules. I've tried recently to use VirtualHostMonster product, but had to face a little problem : - if I load an object and call his "absolute_url()" method, everything is OK - if I load an object, store it in a REQUEST variable or on the stack with "<dtml-with>" or "<dtml-let>", and call "absolute_url()" on this object, the URL is not rewritten. Is there any way to handle this problem ?? Thanks, Thierry