Can you check the logs for the main (authoring) Alfresco server? It's a bit hard to tell from the exception message, but it looks like the PermGen problem might be occurring in the authoring Alfresco, but being passed through to the virtualisation server via RMI, and then showing up there. In other words, I'm not totally convinced that it's the virtualisation server that's running out of PermGen space.
Increasing the PermGen for the main (authoring) Alfresco instance (as described in WCM-795) is worth a shot - the JVM will use 64MB more memory, but other than that there's no down side to trying it out.