Scratch

if someone else does it for you, what have you gained?
I'll tell you the theory (which is very simple) and then you make it. This way you have learnt how to make gravity, and not have to ask on the fourms every time!

The simple idea is this:
gravity is a variable, so make a variable called gravity.
Now, im asuming your making a PlatFormer, if your character is touching the platform, gravity = 0, else gravity changes by negative X- X being the power of your gravity (id suggest a number below -1). Now, change your characters y by gravity, and presto, it works.