H.248 over SCTP Long timer

Hi,

When using SCTP as transport , is it recommended  not to use LONG TIMER 
to remove transactions from response list ?
It is suggested to use SCTP Data acknowledgement to do this. But how 
will this work if  the response is dropped in a queue between the SCTP 
stack and H.248 stack ? If during congestion a response gets dropped 
after reading from sctp socket  but before putting in H.248 stack queue 
the stack is deemed to retransmit teh request.

Thanks,
Vikram