That all makes sense.

This is because the technical options to allow pre-paid customers to make
calls while roaming are difficult. There are two. The first is to use some
sort of callback system, where you dial a special code first and the callback
center makes the call for you and calls you back.

The problem with this is that in many places callbacks are illegal or require
a license which may be impossible for a foreign company to get. T-Mobile when
they were One-to-One in the U.K. had a system like this.

Due to a flaw in the system I lost over 30 UKP in pre-paid money. They never
acknowledged the flaw or refunded the money, but I'm sure I was not the
only one and they decided that the system was more trouble than it was
worth.

They may still have it in the U.K., but the U.S. subsidiary did
not bother to implement it.

The second is a system called CAMEL which is an acronym, but I don't
remember what it stands for. It allows one phone system to use the pay
as you go system on another. This requires contracts to be in place
besides the software and they may not have it.

They may also not bother just to make contract phones worth that much more.

In most of the world pay-as-you go phones are bought by the frugal, the
poor, and for children. In the U.S. the perception is that they are
bought by drug dealers, swindelers and visitors from countries with no
extradition treaties so that when the same $10 in airtime is fraudulently
used by 100 people, the "hacker" and his salesman have faded into oblivion.

This may be not as far from the truth as the U.K. service providers used
to avoid the international stolen phone blacklist and tried to sell as
many pay as you go SIMs to pump up their customer base.

I myself had two used phones sold to me in good faith by a U.K. dealer
who took them in trade. If they had sold them to a U.K. resident they
would have worked, but Orange Israel checks the blacklist.

If your phone is not SP or SIM locked that will be fine. Then you get a
local Brazilian number and pay the local company whatever they charge, but
no roaming rates.

If you have friends that live there you should ask them to get the SIM
for you in advance so that you know your number before you leave.

Note that there are two oddities that you need to be aware of:

1. Brazil uses GSM 1800, not GSM 1900. Make sure you phone can support it.
  The network does not cover the entire country. Make sure you will be in
  a covered area.

2. Brazil uses 120 volt, 220 volt and 240 volt electrical systems. Make
  sure you have the correct charger and plug adaptors for the places
  you will visit. If you don't have the adaptors, most places sell them
  cheaply, but don't expect to arrive on Saturday afternoon and to buy
  one before Monday.

  See: http://kropla.com/electric2.htm

That's it, I hope you understand why now.

Geoff.

I use a V400 with Cingular and I do have roaming, but it is expensive. If
you don't mind having a local number then go ahead and buy a pre-paid SIM in
the country you are visiting. As your phone is unlocked the SIM will work
and you are not having to commit to a 1 year contract. I have a SIM's for
several countries that I visit on a regular basis.