First off, never ever seen this posted if it has been then uhm.... whoops :P, it's pretty simple to do and nothing special really but i thought i'd make a quick guide of how to get on anyway. Also you need an epic mount for this as far as i am aware
Ok get yourself in the position of the picture below
Then face the stall thing and jump towards where the little red mark should be, well thats the area i seem to be able to get up at.
There we go your up ^.^