You beat me to it by one day. See also
unlock help for a downloadable calculator and a real English description of how to do an unlock.
It works fine on my E1550.
Phones: Samsung Galaxy Gio, Motorola KRZR K1, Nokia 1600b
SIMs: 7-11 SpeakOut CA, tele.ring/A1/Yesss AT, Mobal
R.I.P.: UM, UM+