BT (NYSE: BT) has confirmed a deal to buy Ribbit, a Silicon Valley outfit with impressive features for web-based voicemail handling. The price is put at $105 million (£53 million). What Ribbit calls “an open platform for telephony innovation” is built on its SmartSwitch technology that links the phone network with the internet. From there, its web-based Amphibian suite lets users play and read voicemail, call up profiles and lifestream profiles for phonebook contacts and take in-page calls. Developers are also building a number of widgets. BT’s mobile commitments have not been significant since it abandoned its Cellnet JV in 2001, but it is now giving smartphones for the Vodafone (NYSE: VOD) network with some of its broadband packages and Ribbit’s services could come in handy for either its corporate clients or its increasingly connected home users. BT says it will add Ribbit to its software development kit (SDK).