T-Mobile will start to charge 12p for 07744 numbers instead of considering these as part of your inclusive minutes. You can also use 0871 number on T-Mobile which only cost 10p and offer much more destinations than 07744 numbers. Chat about it in - 07744 Discussion Forum

13 Apr 07 - T-Mobile starting to charge 12p for 07744

A rather sad news for T-Mobile users of 07744 numbers that the network will no longer consider calls to 07744 as part of inclusive minutes from 1st of June 2007. All calls to 07744 / 07755 on T-Mobile will be charged at 12p per minute flat rate. While this is still reasonable option for some countries, for others it will be expensive to call from your T-Mobile phone.

This news was released by YourCallWorld (the same supplier who negotiated with T-Mobile initially). They will be releasing some new access numbers which will not be charged 12p per minute but will have a different rate (3p to 8p) depending on destination. We will update our website once these numbers are out.

Remember you can call 0871 access numbers using your T-Mobile at a flat rate of 10p per minute. This works 24 hours a day and seven days of week. This option might be cheaper for some destinations and a good option on weekends.

Details about this news can be found here
http://www.yourcallworld.com/tmobile/default.aspx