2000 passenger door sticks

had my 2000 300m since November, great car but the passenger door sticks when opening from the outside. If you bump the door (like with your knee) while pulling up on the handle it pops right open. No problems from the inside
Is there an easy way to adjust this? I spotted an opening and what appears to be an allen screw just below the latch, is this for adjusting?
Any info would help....
bam

I have never heard of a door hinge problem with our M's. You didn't say if it was a front or rear door. Check a couple of things: 1) at the bottom of the door are three screws holding the plastic door panel in place. Sometimes these break and need to be fixed. If this is the cas get back to me and I can help; 2) check the gasket and see if it need to be pushed back into place. Sometimes it gets pulled out a little. Maybe spray a little silicone on it to make sure it doesn't cause sticking.