blackberry bold international issues

[LD1776]

looking for any assitance. I have a blackberry bold 9650 that is from the US. I am in the UK for work this week. I called Verizon prior to my departure and set up my international plan. However, now that I am here,  my phone is saying "insert SIM card".  I have tried both a soft re-start (i.e. shutting the phone off) and a hard re-start (i.e. removing the battery and SIM, then re-inserting) but the problem remains. Additionaly, when I turn on the mobile connection, it says SOS.

Is there anyone else who has experienced this and can assist? I tried to call verizon international for assistance, but after 25 minutes on hold, I had to disconnect.