I created two address locators in a shared file gdb which I then published as separate geocode services. After performing several test searches in ArcMap against the gdb locators and the services, everything seemed to be working correctly.
I then created a composite address locator in the file gdb, composed of the two separate geocode services and then published the composite locator on the server. When I get to the Service Editor and Analyze, the only warning I get is that the composite locator will be copied to the server, even though the gdb is accessible to the server. This is a minor issue though, as covered in the answer to this question.
The problem occurs after clicking Publish. ArcCatalog hangs for a few seconds, then crashes. I rebooted the machine and tried again, and the same thing happened. I then tried from a different admin account, and it crashed again. A post on the ArcGIS forum indicates that this might be an issue in ArcGIS itself when trying to include online services in a composite locator service.
I'd like to know if this is possibly a bug, or if there is some workaround or settings that must be changed. I left all the default settings unchanged. I'm using ArcGIS for Desktop 10.1 and ArcGIS for Server 10.1, with SP1.