I'm using Nokia E70 (updated to the latest firmware), I set it up to work with sipgate via WLAN and it works good.
I would also like to be able to connect to sipgate via 3G connection. I tried editing the "SIP settings" and changing the "Default access point" to be my 3G connection. After that I typed in a number and selected internet call. The phone informed me that I'm not registered with Internet telephone service and asked whether to connect. I clicked yes and after about 3 seconds I get a "Unable to register to service" message. The phone didn't even connect to the 3G connection (the icon doesn't appear, no log entry). If i try connecting to the service via "Internet tel." option from the "Connect" menu my 3G connection is not listed, only my WLAN connection is there. Since the phone isn't connecting to the 3G connection, I'm guessing it's a phone, or phone setup issue...