it will be interesting to know if you were charged or not over UMA. i also wanted to try this since i travel a lot but didnt give it a try while reading on wikipedia that subscribers may be charged with UMA (unlicensed mobile access) or GAN (general access network). While on travel and calling back office i use 3rd party mobile voip apps that are cheap and give totally free calls when in hotspot. so it makes sense to use them since on official tour you always get hot spots in hotels, airports and you can connect back to your office...this can work for home if you have setup wifi in your home as well. if there is no wifi access then their call rates are cheap since they utilize VoIP. i have been using truphone and vopium interchangeably though i have installed both of them but using later nowadys.
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