Undeploying Glassfish web application does not disconnect from ObjectDB

Glassfish3.1.1
Netbeans7.1

ObjectDB 2.3.7_19

If I deploy a web application to Glassfish using ObjectDB as JPA provider, then undeploy, I can't access the database file in the ObjectDB explorer, the explorer claims the database file is being accessed by another process. If I restart Glassfish I can open the database file in the ObjectDB explorer ok.

Are you using ObjectDB in embedded mode?

Apparently undeploying a web application from GlassFish doesn't close the EntityManagerFactory, and consequently the ObjectDB database remains in use (and in embedded mode - no one else can use it).

It is unclear what can be done (if at all) on ObjectDB side in order to solve this problem.