Adobe RUM with multiple versions of Creative Suite

I am having an issue when running RUM on computers with multiple versions of CS installed. The computers are OS 10.7.4 and have CS5, 5.5 and 6 installed. When I run the RemoteUpdateManager command, a get a return of 'There doesn't seem to be anything to update', even though there are a slew of CS6 updates that need to be installed. On computers with just CS6 installed, RUM behaves as it should.