Problems sending mail from Address Book

[mfacey]

I can't send emails to groups I have created in Address Book. When I right (/ctrl) click the group name it gives me the option to Send Email to [groupname]. However when I click this nothing happens! I'm not in editing mode. and yes the option to send mail in the right click menu is not faded out.
Do I need to select my mail application as the default anywhere?

Thanks.