It's possible by unlocking code.I found the site http://www.onlinegsmunlock.com/sony-ericsson-t610/rs7wp9/ .This is the unlocking site which provides the unlocking service at cheap price.It also guides you throughout the process.
pooja, June 2010
hi i forgot the unlock code for my motorola rival i ned help
johnny, September 2009
You need a cable with a terminator dongle available on e-bay for around 15 quid