Wiki plugin. Email notifications not sending

Hi guys.

Firstly, thank you for creating excellent plugins. Long time lurker and now made the plunge and bought your monthly package. Looking forward to working with you.

I do not receive notification emails when changes to wiki pages are made. I have...

Enabled notifications on wiki page when editing
Enabled notifications by typing my email address in when viewing same wiki page
Installed, configured and tested easy SMTP plugin for Wordpress
Read this post and tried suggested plugins
http://wordpress.org/support/topic/wiki-e-mail-notification-not-working.
I am able to receive emails from contact forms

Thanks again and I will appreciate any advice you can offer.