My son has a Sony-Ericsson z525a and will be using it when he travels to
Spain next month. Cingular/AT&T has assured us that the phone has the right
frequencies to work overseas. We have decided to buy a Lebara Spanish SIM
card to use in the phone while he is overseas. That will greatly reduce his
cost of making outgoing calls.

The phone is currently locked, but Cingular gave me the unlock code and a
procedure to follow in doing the unlock. My question about the procedure is
that it says to remove the Cingular SIM card and put in the new SIM card
BEFORE doing the unlock commands. Does this mean you can't unlock the phone
while the Cingular SIM is still in it? Or is there some other reason they
said to do it this way?

The procedure they gave me is the following:

1) Power off device and remove AT&T SIM card.
2) Insert SIM card from another wireless carrier.
3) Power on the handset.
4) Press the Left Arrow (<) button.
5) Press the star (*) button twice.
6) Press the Left Arrow (<) button.
- display indicates "ME Lock"
- wait approximately 3 seconds.
- the display indicates "Network" and a picture of a closed lock.
7) Press Yes.
- the display indicates "Unlock?"
8) Press Yes.
- the display indicates "Enter NCK"
9) Enter the SIM Unlock code.
10) Press Yes.
11) The handset displays "Network" and a picture of an open lock for three
seconds and then reverts to the main display. The handset is successfully
unlocked.

At 23 Apr 2008 10:51:52 -0400 Rick wrote:
> My son has a Sony-Ericsson z525a and will be using it when he travels
> to Spain next month...

> The phone is currently locked, but Cingular gave me the unlock code
> and a procedure to follow in doing the unlock. My question about the
> procedure is that it says to remove the Cingular SIM card and put in
> the new SIM card BEFORE doing the unlock commands. Does this
> mean you can't unlock the phone while the Cingular SIM is still in it?


Depends on the phone. Some phones can't be unlocked with their regular
SIM, because the phone" sees" no problem with the current SIM and won't
start the unlock routine.

Some phones can be unlocked with their regular SIM, some with no SIM at all
in them, and some require a "foreign" (to the carrier- not necessarily a
foreign country!) SIM installed.

The real problem is that most phones only give a few tries to get it right
before the unlock proceedure "self destructs" disabling the phone from
being unlocked except by the manufacturer. When I tried unlocking my first
phone (a Nokia 8290) I used up 2 of 3 allowed attempts by not reading
carefully- the instructions specified removing the SIM, but I'd left it in.

If you don't want to risk activating the Spanish SIM's service early, find
a friend who uses T-Mobile and borrow their SIM for a minute- the unlock
proceedure will not hurt or alter the SIM in any way.