iebel adapter uses Siebel COM control to connect to Siebel backend. Since Siebel COM control objects work only in STA mode, Siebel adapter creates dedicated thread for each connection being opened to server. Sometimes this thread hangs around if Siebel adapter is configured to use ASDK's connection pool and client didn't explicitly call ChannelFactory.Close(). By default this thread will be active for 1min and this setting is control via binding parameter "IdleConnectionTimeout" (or "idleConnectionTimeout" config entry if configuring via config file). Till this thread is alive, the adapter host process doesn't terminate. This issue will be seen where client doesn't call ChannelFactory.Close().