Internet giant Yahoo has agreed to acquire California-based Dialpad, which develops a so-called 'soft phone'.
Dialpad's Chameleon application allows users to place telephone calls from a computer to a regular telephone number using Voice over IP technology.
The company offers a series of subscription plans with rates as low as $0.017 per minute for calls within the US or between the US and Europe.
It also provides a pre-pay service using calling cards, allowing users to place calls from a regular telephone, but has stopped taking orders for this service.
Yahoo plans to use Chameleon to expand its portfolio of VoIP services. The Yahoo Messenger client already supports VoIP calls between two computers, but does not allow users to call regular telephone lines.
Terms of the deal were not disclosed. Dialpad was founded six years ago and has about 40 employees.
Yahoo has a partnership with BT in the UK to deliver its instant messaging software as part of the BT Communicator soft phone. Chameleon could potentially compete with BT's software.
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