how to network unlock galaxy ace S5830i ?

[chenks]

got a galaxy ace S5830i that is locked to one network.
are there any working instructions on how to unlock it?
it's running 2.3.6

 

[chenks]

managed to sort this.
rooted the phone (which was surprisingly very easy), then used an app in the play store called "galaxy toolbox" by "doky".
worked perfectly.