you mean the ne/sw cursor ?
this particular application didn't really warrant the forth cursor
there are 3 cases:
you are on the vertical divider
you are on the horizontal divider
you are on both dividers
tell me what the 4th case is, and i'll put the cursor on it

(and, before it hits the page, i am not counting "you are not on any divider" as a case - lol)