Just a warning for Treo 600 users with unlocked Treo 600 phones on the Fido
network (like me).

I attempted to update the firmware of my unlocked Treo 600 phone using the
following link:
http://www.palmone.com/us/support/downloads/treo/treo_600_updater.html
(http://tinyurl.com/3c356) and my previously unlocked Treo 600 phone became
locked. Since I have a Rogers SIM, I tested it and my previously unlocked
Treo 600 phone became locked to Rogers. During the updating process, the SIM
in my Treo 600 was my Fido SIM.

Since my phone was unlocked, I picked the "Other Carriers" entry:
http://www.palmone.com/us/support/downloads/treo/treo_600_updater_other.html
(http://tinyurl.com/2py5s)

Going to the following screen: http://tinyurl.com/ywgln it says that it
won't allow me to install the wrong version... well the version that I
downloaded did install without any errors and after following the
instructions my Treo 600 became locked.

I called PalmOne and they told me to call my service carrier. I informed
them that since I didn't buy the phone from them, they wouldn't be much
help. Even if I did buy the phone from my service provider, service
providers will generally not unlock the phones for customers. My service
provider by the way doesn't sell the Treo 600 phone.

If you have an unlocked phone, updating the firmware using this program
might lock your phone (like it did to me).

I'm now going to have to see if the company I purchased the phone from can
unlock it or whether PalmOne can help me (I placed a support request but I'm
not very optimistic that they will help me).