asterisk users - Jun 2005 - Cell Phones reporting internation calls

I have two different inbound DID providers and on each network I have 
had reports in the last several days from callers that when they try to 
call me from a cell phone their provider reports that they are trying to 
make an international call and thus doesn't let them complete the 
calls.  In each case these have been local calls for them.  Has anyone 
else had this experience? 

MARK.