Rotating in the Perspective viewport

 From:  Frenchy Pilou (PILOU)
10378.2 In reply to 10378.1 
Click one time the "Reset" Button
Mouse Wheel for have the size wanted
Mouse Wheel Click pressed + Move the mouse for pan anywhere you want
(better if it's in the middle :)
*** now you can use the "Rotate" icon *** ;)