My name is Denis. I worked more than 3 years in telecommunication in Russia, I've had Senior Core Network Engineer position. Now I’m client of Saunalahti. And unfortunately I have a problem with your 3G-2G and 3G-3G HANDOVERS.
When I set “DUAL MODE” (GSM and UMTS) in network settings of my phone, I was having problem with incoming link – after moving to another place (in Helsinki or Vantaa) my friends and relatives could not connect with me. When I set “GSM” in network settings of my phone I had no any problems with connection at all.
I think my phone does not make LOCATION UPDATE under new RBS/BTS, because your engineers do not create some required HANDOVERS between RNC and BSC (or maybe even between RNCs). So it is fact that in dual mode after some moving my phone lose registration (I guess that in that moment my phone is not correctly registered in your MSC/VLR).
My wife had the same problems. And problem was also removed when I set “GSM” mode in settings of her phone.
I have NOKIA N95 8GB model, my wife has NOKIA 5800 8GB. Both phones were bought in Finland. That’s why I think problems can not be inside our phones :)
UMTS mode is more preferable for us because speed of mobile internet is higher and one is cheaper, and we can make even video-calls :)
If you will be going to trace my number: my MSISDN is 358452750112.
Thanks for your time,