I got a text message on my old mobile phone (which I’ve moved to PAYG, to keep the number active), purporting to be from Vodafone, received 15-Sep-2009, and stating:

Thanks, for being a Vodafone customer, we'd like to give you £1 free credit. Just text REWARD to 97888 for free by 24Sep09. To stop texts send STOP to 9774

This made me immediately suspicious, as it’s trivial to fake the sender of a text message to appear to have come from “Vodafone” or whatever name/number you like, and it sounded like a reverse-billing SMS scam.

However, I recognised 9774 as the number Vodafone really use to stop receiving texts, so if it was a scam, they’d at least done their homework.

Googling reveals that the shortcode 97888 is indeed a Vodafone number, used, among other things, to request their “Vodafone Passport” deal, and turns up a forum thread on the subject.

(Amusingly, the forum thread includes a nice little rant:

I GOT NOTHING and its annoying i cannot believe voda sending these messages then again , yes i can..
its like the annoying canvassing phone calls.
can we do anything to stop them ? from voda.
one annoyed voda customer.

Um, what? The clear, simple “To stop texts send STOP to 9774” at the end of the message too hard to understand, perhaps?)