[X4U] random addressees showing up as "person"@mac.com

[Michael Elliott]

I've got a strange question and was hoping that someone might know the  
answer.

I've got a person that emails me and about 20 others.  Let's call her  
Jane Smith.  Whenever she does, her "from:" email is listed as "Jane  
Smith"@mac.com.  Including the quotations.  I know that she is NOT  
using .mac as her email.  About 3-4 of her addressees are also listed  
as "John Smith"@mac.com and "Dr. Jones"@mac.com.  Other addressees on  
both the internal domain and domains like flash.net and yahoo.com are  
all listed normally.

I'm sure she's using Outlook.

Any ideas as to why her email address and those few others are shown  
that way?

Thanks