RND, uncheck "Subscribe to this post" under the quick reply box? Post, then check on another thread to see if it's reapplied? (dunno... just throwing out thoughts.)
Doh... better one for you.
At the top, where it says "Welcome Redneckdude (Sign out | Options)"
Click Options -> View All Options
Uncheck "Auto subscribe to new posts and replies you create" and save.
See if that does it?