Does someone know how to either port or use the Robert Penner's easing equations ? http://www.robertpenner.com/easing/easing_demo.html

Not exactly, put you might want to have a look at the mapping library. Some of the things in there look along these lines.

Hey thanks ! I actually found a glimpse of what i'm looking for using a lop~, brillantly demonstrated by Thomas Grill here: http://markmail.org/message/jn6ziethj2ghx47w