I got into a weird error connecting CF Builder 2.01 to CF10 RDS to get some nice DB interactions going.  I was constantly getting the error:

could not initialise class com.adobe.rds.core.services.Messages

Both in the logs and as a nasty error popup.  This is reproducible using virtual hosts with Apache, I did not experience this on the standalone CF10 at all.  In Apache I have the CF10 connector installed globally, so I would assume it worked for ALL virtual hosts.  However, for some reason the above error is due to a connector issue.  To fix this, and I have no CLUE as to why it fixes it, but it does. Is to add the following to your virtual host configuration file:

JkMountFile "/Applications/ColdFusion10/config/wsconfig/1/uriworkermap.properties"

This will fix the issue, so go back to builder and click on the refresh server and voila! Issue is gone!  Can someone explain me why?