Orange SMS Spam

I used to be very happy with the service I was receiving from Orange. However lately I just seem to be getting constant SMS spam from them to my mobile phone advertising various services.

I signed up for a free three month trial of their WAP services. Getting rather fed up of the SMS barrage from them, mainly relating to this free trial, I sent a STOP message through to the reply number and received a confirmation that the messages would now stop and hoping I enjoy the rest of the free trial. However, today I've received another SMS from them advertising voice help for the service.

What annoys me even more than receiving these messages is that each time I send STOP messages, it costs me money. Maybe that is Oranges plan? If they are doing this to everyone they must be making a fortune (as well as alienating their customers).