Docky disappears in multiple monitors configuration

(This problem affected me with Gnome-Do's Docky, so I copied a little of the description).

The problem is a little bit hard to descript, so I made this screencast:

http://www.youtube.com/watch?v=qnvyeJyXfps

I have two monitors with different resolution (1200x800 at the left and 1280x1024 at the right), AND they are Top-Aligned (like this [1]). If docky is in the left screen (the small one), and there is any window there, docky disappears (because of intellihide) and I can't make it back moving the cursor to the bottom; this doesn't happen if there is no window in the left screen.

If docky is in the right screen (the bigger one), everything works fine.

If both monitors are Bottom-Aligned (like this [2]), docky's behavior is fine too.

[1] http://img412.imageshack.us/img412/4193/topaligned.png
[2] http://img267.imageshack.us/img267/9420/bottomaligned.png

Is there a way to detect if the mouse cursor is at the bottom of the real monitor's screen, not the virtual one?

Thank you!