Reliable software for unlocking an iphone?

I have been given a second hand iPhone 3Gs by a relative that is locked to Orange however I have a sim for another network.

Does anyone know of reliable software to unlock an iPhone? I have tried the following but they do not work:

- The software (iPhone 2, 3, 4 unlocker v1.1) is demonstrated in this video along with a link however what is not pointed out is that in order to obtain the serial number you need to complete an online survey. After doing that you are provided with a serial number that does not work. I suppose the video poster must have got some friends and/or fellow spammers to post good reviews in the comments.

http://www.mediafire.com/download/atbrl9u66v3lptm/IPU±+Updated+++Working.zip

This file comes in a zip that is password protected. In order to obtain a password you need to complete a survey after which you will be supplied with an incorrect password.

So neither of these have solved my problem but I have gained a little satistfaction by reporting the spammers to Youtube and Mediafire respectively.

Added (1). Recovery mode and restore with iTunes didn't work. Now it seems I can't do anything at all with the phone unless I get a sim card from a supported carrier (i.e. Orange) or get them to unlock it. So I guess I'm just going to bite the bullet and hand over £20 to Orange.

Please DON'T try that at home.

Switch you iphone to recovery mode. Then click restore.