Unlock Samsung Galaxy i5500

I followed this guide:
http://forum.xda-developers.com/showpost.php?p=12099386&postcount=6

To gain root access (required) I used SuperOneClick:
http://forum.xda-developers.com/showthread.php?t=803682

You will also need adb shell.

I. Root the phone.

II. Use adb to extract some information:

adb shell
su
cd /

# remount the root filesystem with read and write access
# can also be done with Root Explorer
mount -o remount,rw /

# on other systems you may have to explicity specify the filesystem
# mount -o remount,rw -t rootfs rootfs /

mkdir /efs
mount -o nosuid,ro,nodev -t vfat /dev/block/stl5 /efs
# on another phone /etc/fstab says:
# mount rfs /dev/block/stl5 /efs nosuid nodev check=no

cat /efs/mits/perso.txt
umount /efs
reboot

III. Next:

You will see some numbers: In my case 20404 for Vodafone NL.

Then you will see your SP unlock code followed by some 000000000 codes and another code. Write the first one (and second just in case) down.

Shut down the phone and put it a "locked" sim. Start your phone, input the pin, and when asked for a unlock code give it the first code. Your phone is now unlocked.