stopping unwanted mobile texts

[Mattk]

my son has a mobile phone on pay monthly contract that i pay for(of course !).despite warnings from me he keeps using premium texts.i have tried simply texting 'stop' to the senders number but it does nothing as they will only recognise an exact stop message.i know relatively little about mobiles but is there a way of finding out how to stop these messages ie what is needed to be texted to stop them ?

[Gandy]

You can contact ICSTIS (Independent Committee for the Supervision of Telephone Information Services) and get advice from them. The "stop" command was introduced on 1st August 04 but has not yet been adopted by all as their software simply cannot undersatnd the command.