Email Post Subscription Problems

I posted this topic/problem in the Plugin/Hacks section but haven’t had a response. I need some help with this if you please.
I can post via email just fine using the default WP functionality. However, the current subscription/notification plugins (including Update Notify and Subscriber) don’t work when you email in a post. They work fine when you post through the admin interface, but somehow they’re not getting triggered and I’m wondering if it’s something to do with the core functions or if it can be fixed in the plugins or the wp-mail.php without getting into the core.
Anyone have any experiences with this type of (dis)functionality?