3.4.5.1.2.2 Receiving a TXUSER_SETTXTIMEOUT_MTAG_SETTXTIMEOUT Message
When the transaction manager communicating with an application facet receives a TXUSER_SETTXTIMEOUT_MTAG_SETTXTIMEOUT message, the transaction manager communicating with an application facet MUST perform the following actions:
If the connection state is Active:
Set the connection state to Modifying Timeout.
Signal the Set Transaction Timeout event on the Core Transaction Manager Facet with the following arguments:
The transaction object referenced by the Enlistment object referenced by this connection
The dwTxTimeout field from the message
Otherwise, the message MUST be processed as an invalid message as specified in section 3.1.6.