Block Senders for Outlook 2010 - block address with more than one @ in address

Newer spam now contains an address like <admin@appmarkg.netprincesscruises@email.princess.com>.  When I right-click and select block sender or block domain, I get a message that the email address or domain is not valid.  I am using Outlook 2010 ver 14.0.6126.5003   SP3.  

Have spammers gotten found a hole in the junk mail handler?