users not getting email

I tested this back in April and it worked. Now, with the upcoming auction for an important client coming near – I cannot get it to work! The emails (after approval) are simply not being sent. Nothng is happening. There is nothing in spam or deleted items. I am not using aliases, but real email addresses. Don’t know what’s going on. Help!

http://wordpress.org/extend/plugins/new-user-approve/