I have BT Broadband Talk as part of my broadband package. I use it occasionally from the UK but there isn't a lot of point as the calls aren't free, however I can see its appeal when abroad. I always thought though that it wasn't accessible from other ISPs or Mobile network operators? Certainly from the SIP client on my mobile phone using Vodafone I can't register, however at home when I enable WiFi on the phone it happily registers and I can make and receive calls from my Broadband Talk number. Also when at a friends house who also has BT Broadband I can register and use Broadband Talk, but at my sisters who has Orange broadband it doesn't work?
I assumed the ISPs/Network Operators blocked SIP access to the BT Broadband Talk server?
my daughter is on Orange and my HTC desire using sipdroid works with my bttalk - just need to log in to her network
Hmm... I am sure this didn't work last time I tried this - however I'll check next time I am there. I can also check at my mums later who has TalkTalk..
it may be the router - my daughter uses a netgear