I have been here 3 months now and am still trying to sort out my phone
It is currently locked with orange, I have contacted them several times via e-mail as found it impossible to get through on the phone as I am no longer a current customer. After receiving several pieces of wrong information from them I have finally been told they can unlock for me for 20 pounds and will contact me via phone to do so. I am still waiting watch this space.
I dont want to change my phone as it is the LG shine which is quite new over here. I have been told by people over here it tends to be UK companies beginning with O - ie orange and o2 so my advice would be to check with your company before you leave to save you a lot of trouble.