This is the best response I can offer:
Cingular v. T-Mobile
My opinion Cingular v. T-Mobile is based on many factors. First, I have both SIM cards at my disposal. I have a Cingular on its International Blackberry Plan. My wife has a T-Mobile SIM. We are Americans, but she is based in Dubai and I go back and forth. In the last year, we have collectively been in the US, Canada, Guatamala, Belize, Mexico, England, France, Germany, Austria, the Netherlands, Kuwait, Lebanon, Israel, Egypt, Turkey, Oman, Hong Kong, the UAE, Macau, and Mainland China. I have also had Cingular?s international division concede the point to me, but I?m sure that it wasn?t official.
Here is a link to Cingular?s global roaming page.
http://www.cingular.com/media/roaming_gen#country
Here is a link to T-Mobiles:
http://www.t-mobile.com/International/Roam...b_RoamWorldwide
You might be able to get printed brochures at company stores with the full list.
The Nokia E61
It is Symbian, not Windows. I suggested the phone because of its multiple bands and connectivity. Also, it has built in VOIP which can prove helpful as well.
Countries Discussed
Problem Countries Listed.
South Korea. South Korea doesn?t use GSM. You need a 3g phone like the Nokia E61. According to GSM World, neither South Korean provider has declared any roaming agreements. Donald Newcomb who is a regular to this forum has managed to use his phone in Korea and will probably be able to explain whether the the statements on GSM World are correct. By the way, I?m reading from:
http://www.gsmworld.com/roaming/gsminfo/cou_kr.shtml
GSM World is the GSM umbrella organization.
Dubai. I?m surprised about his comments on the UAE. I am there so much that I signed up for their E-Pass so that I don?t? have to go through customs. My E61 works there easily on data and voice. Sometimes, Cingular takes a couple of hours to register on Etisilat.
Nepal. A year and a half ago when I researched Nepal, they had almost no roaming agreements. I?d be shocked if they had any data services.. According to their filing with gsmworld.com.
http://www.gsmworld.com/roaming/gsminfo/ser_npnt.shtml
Neither Nepalese carrier lists roaming agreements with the US, but they do list roaming agreements with O2 and Vodafone in the UK.,
Tibet
China Mobile has a tiny amount of coverage in Tibet:
http://www.gsmworld.com/cgi-bin/ni_map.pl?cc=cn&net=ct
02 out of the UK is the only listed roaming partner of China Mobile. I can?t believe that, but that is what I read on the GSMWorld website I couldn?t turn up a China Unicom map.
Why I Mentioned England
02 out of the UK has the most extensive roaming agreements in the world. At least that is my opinion. I was suggesting that you might want to have your UK office obtain a UK SIM for your president as a backup. It is the gold standard. If need be, you can get a US number which will call forward to the UK number.
As a matter of fact, a call forwarding number might be perfect for this guy. That way, if he has any problems, someone back in the states can reset the number to ring on the backup SIM. Call forwarding his Cingular SIM will only work if he is able to get it active on the network.
You can get an 02 SIM with international roaming active from mobal.com, but they mark up the prices significantly. If you have a presence in the UK, get a UK SIM through your UK office. A good call forwarding number to a UK mobile is from voicestick.com. Not only are the rates reasonable, but the service connects quickly. It also places a recording saying "please wait while I connect your call." Since there is sometimes a small delay before connecting to a roaming mobile, this lets the caller know to be patient a second or two longer.