I check MP when I'm out & about on my blackberry, but I can't figure out how to post or reply or anything. I can type in the reply box, but I can't find the "post" button or whatever. Am I missing something?

The quick reply box isn't active until you click the quick reply button under a post. You might be able to type into it anyway but it won't do anything.

Look for a "Quote" button under a post or a "Post Reply" button under a thread.

No, no, I got that... it's the "submit reply" button I can't find (sorry, couldn't remember exact name) once I've actually quoted or whatever.

Beyond that, I don't know--I haven't used the Blackberry Web browser. I use Opera Mobile on my Windows Mobile device and the button is right there. Maybe search or ask on a Blackberry support forum?