OCS Public IM format issue

Some users can use hotmail address which is related to another domain.
ex:erkan.sezgin@hotmail.com is bound to erkan.sezgin@yahoo.com
If you want to add this address to MOC 2007 ,you need to add this address as "erkan.sezgin(yahoo.com)@msn.com".
But you cannot use tools menu-->add contact process.
tricky point,use search box at the top of Moc window.