sql trigger unscribption problem string manipulation

i have a messsage sent from a mobile user ..
when he send to me a msg  "u 1" unsubscribe service 1 to user...
and u 2 unsubscribe service 2 to user after

                        IF @message IN ('unsubscribe', 'u')
                        BEGIN                              
                              -- Deactivate all accounts
                              -- The user account is active, deactivate it
                              UPDATE subscriptions SET subscriptions.active = 0  WHERE msisdn = @msisdn

END

the @ message maybe it's : "how are you"  and "u" is on message ?
so what is the solution ?? i use regular expression..

so how i can solve it because i have many services and each one is related to numbers
so ???

if message is "u X" where x is a service code number