Frozen Assets in US

I have had my brokerage accounts frozen in the US as they have identified me as living in Ireland - I actually live in Scotland.  I cannot purchase new holdings or make deposits although I can spend my own money on paying bills.

The letter reads "we can no longer continue to provide investment services for these accounts because one or more of the address associated with these accounts are located in a certain country outside the United States."

I tried to move to a full-service brokerage but they said the same thing?  What the heck is going on?  This is my retirement fund and I need it to grow or else I am going to be working until I croak!

Anybody got any ideas or had a similar situation?

You might not have seen these?:
http://americansabroad.org/files/7013/3589/7836/banka.pdf
http://www.prweb.com/releases/2013/2/prweb10422310.htm
http://bsmlegal.com/PDFs/American%20Citizens%20Abroad.pdf
http://www.aaro.org/banking-services-denied-2010

You might find it difficult to open a new account if you don't have a US address. I'd talk Vanguard, Fidelity or Schwab. Those companies definitely allow accounts to be held by people living abroad.

What is the retirement account you have? A 401k, IRA etc?