[Zope] __before_publishing_traverse__: VHM put into TraversalRequestNameStack

Hi, you all, I'm running several virtual hosts (Zope 2.6.2) behind an Apache. When I access a virtual host, the __before_publishing_traverse__ method of my site class sees a slash and the VirtualHostMonster on the top of the TraversalRequestNameStack (indexes -2 and -1). Is this a bug, or is it a feature I should rely on? Thanks, Tobias