Text Message Cost

[#1]

I've just checked my itemised bill for the period ending 21/2/10 and found I've been charged 20p per text for two messages sent from my landline in that period.
The tariff states that it's a fixed fee charge of 10p/message.  
From this page:
The following call types are not subject to a set up fee:
Inclusive calls
Fixed fee calls
Calls to Plusnet Support
Is the 20p charge a mistake or are texts subject to the 9.3p connection charge? (As far as I can tell from the tariff,  text messages aren't subject to a connection charge.)

[#2]

Hi Paul,
It is a mistake, you're right - it's a fixed fee call and shouldn't have a setup charge. I'll get that refunded for you and get a problem raised so this stops happening, thanks for the heads up.

[#3]

Thanks for that Matt - thought it might have been a mistake