I'd recommend installing Telefonica and then get your UK calls free by follwing the instructions as per this site:
www.0044.co.uk I've had Telefonica installed today, and I've come across this website - I've tested it and it doesn't affect the quality of the call (no delays etc).
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ANNALISA TURNER-STERLING
BUSINESS DEVELOPMENT DIRECTOR
WWW.YOURMARBELLA.COM
+34 663 890 958
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MSN & E: ANNALISA@YOURMARBELLA.COM
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