Baker, who was recently voted the fourth most recognisable voice in the UK, behind the Queen, Tony Blair and Margaret Thatcher, is also known for his part in recent film version of 'The Magic Roundabout', where he voiced the role of Zeebad.
From January 31, text messages sent to landlines will be delivered as voice messages by Baker following five months of preparation to produce the voice from start to finish.
Baker spent 11 days recording every single sound in the English language with up to 11,593 phrases recorded covering their different contexts.
These were then broken down into combinations of sounds that could be separated and reassembled by computer to make new words following the rules of English language.
The service will even let the sender text rude words and phrases and has been programmed to recognise abbreviations. Even text speak such as "gr8", "cu 18r" and "smilies" like :-) will be spoken. If "xx" is put at the end of a text, Baker will say "kiss, kiss", or four or more "x's" will make Baker say "lots of kisses".
Gavin Patterson, BT group managing director of consumer services, said: "As one of our great British icons, Tom appeals across the generations, for his role as the fourth Doctor Who, more recently as the narrator of 'Little Britain' and as Donald McDonald in 'Monarch of the Glen'."
He added: "He's the perfect choice to be the new voice of text, showing everyone -- young and old -- how easy and fun it is to send and receive texts on your home phone."
Baker said it was a big responsibility to be Britain's voice of text, but an appealing one all the same.
Baker said: "What appeals to me most is the thought that I will be bringing good news to people whether it is a cheeky message, a birthday greeting or just a quick hello. Whatever it is, hopefully my voice will bring a smile to people's faces."
Around 230,000 BT customers are already registered to send texts from their landline with BT Text and an average of 1.4m texts are being sent to landlines each week.
Since it was first introduced in 1995, the text craze has grown rapidly and in 2005, 82m text message were sent each day in the UK. The Mobile Data Association predicts that daily usage will hit the 100m mark in 2006.
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