VSTO, OL2007, C#

From our Add-in, most of the time mail.Recipients[1].Address works to return
the recipients email address as say

However, I noticed the following was returned for mail.Recipients[1].Address
this morning from one site instead of an email address:

/O=COMPANY1/OU=FIRST ADMINISTRATIVE GROUP/CN=RECIPIENTS/CN=SMITH

I assume it has got something to do with the user being on exchange? Is
there anyway to simply get the email address?