Importing adl causes adapter to stop subscribing

I’m running ES 5.0.1 on Solaris 2.8. What happens is that when an import of an adl file is done through the Enterprise Integrator, an adapter will often stop subscribing to a document. It can happen to a JDBC adapter, an IO adapter, an Oracle adapter, and to a lesser extent, the XML adapter.

This is verified through the Enterprise Monitor trace window. I can see an adapter publish the document, but the adapter that is supposed to subscribe to the document never enqueue’s or receives the document.

Checking the adapters client group properties still shows the document in the Can Subscribe tab.

All we have to do is to restart the adapter and all is fine, however we usually do not know there is a problem until much further down the road. Has anyone encountered this behavior before?