CachedConnectionManager - inUseConnections not correct

For CachedConnectionManager service debug option is
enabled to monitor connections.

<!-- Enable connection close debug monitoring -->
<attribute name="Debug">true</attribute>

Using jmx-console, if we look at the "inUseCount"
property. The number displayed is not consitent with
the underlying connection pool. "listInUseConnections"
shows stack traces for connections that have been
closed long back. It take a long time for the
"inUseCount" to drop down, but never drops to 0 even
after the connection pools correctly show inUseCount as 0.