I am having problems with the FastPath tab disappearing on Spark

We have just setup Spark / OpenFire and are trying to test WebChat functionality. Every once in a while we have noticed that the FastPath tab on the Spark client disappears. We have noticed the following entry in our server log that appears to coincide with this problem:

"java.sql.SQLException: Violation of PRIMARY KEY constraint ‘fpAgent_pk’. Cannot insert duplicate key in object ‘fpAgent’. "

We have restarted the Plugin on the server, but those personnel that don’t have access to the FastPath tab no longer have Chat functionality. Any help would be greatly appreciated.