[reSIProcate] Unable to shutdown DUM during retransmission of MESSAGE requests

[Dmitry Semyonov]

Hello.

Consider the following scenario.
 * Send MESSAGE to nowhere.
 * DUM starts the series of retransmissions.
 * Shutdown DUM before onFailure() is called due to retransmissions 
timeout.

In this case DUM never exits.

I even tried to call ClientPagerMsgHandle->end() before shutting DUM 
down with no luck. (I.e. I was not able to force transaction end.)

-- 
...Bye..Dmitry.