VMM control tasks
There is an internal module of the workspace service that governs what tasks are launched when a particular action is required. For example, when the service engine determines that a "Start" action is required, a particular implementation of a "WorkspaceTask" is launched, keyed by the type of action. This "Start" action task may be defined as something that does not call workspace-control anymore, for example.
You can exploit this layer of indirection by creating your own task set that does anything you want at the different points in the VM lifecycle (or perhaps does something simultaneously).
See the org.globus.workspace.xen.xenssh package and the org.globus.workspace.service.impls.async package (for example, the RequestFactoryImpl class).
(This one is more hands on than the other plugins)