This will probately not work with the BF 2142 Engine.

I like Bunnyhopping. In Unreal 2004 it's a cool thing to show your UEBER-5kill in movement.
I don't like it on shooters like BF2, BF 2142 and First Strike - it looks unreal.

In the (Star) Wars Movies the (Storm) Troopers don't jump around an die like a rabbit on speed, they stand and deliver or croutch behind cover and die like a Man, right ?

Sad fact is, a game like BF2 and BF 2142 and First Strike needs a jump function - to jump over obstacles, or jump from one roof to the other.
But with the jump function you can also bunnyhop.

But in games jumping is easier whan in real life, you just simply hit the jump key and your Soldier jump. Hit it multiple times per minute, an he jumps like a rabbit.

IMHO a possible solution to avoid this without stripping the "jumping over obstacles function" is to change the way jumping works:
Instead of "hitting a key and instant jump" "Holding the jumpkey, relase to jump".

By holding the jumpkey a bar gets loaded, if you release the key your soldier jumps.

If you hold the jumpkey long, you get a high jump, if you hold it short you get a low jump.
So you can still jump over a low obstacle like the stairs on MosEspa, or over high obstacles like the  destroyed walls of the ruins around the corvett crash side. 

The distance of the jump should be calculated by holding the jump key and moving / running.
So if you want to jump from a roof to an other you must sprint to the edge of the roof, holding the jumpkey an releasing it in the right moment.

The Bar limits the power of the jump - so holding the jumpkey for 5 Minutes don't allow you to jump from the ewok village to bunker entrance

And hitting the jumpkey multiple times per minute only gives you very low jumps, not high and far enought to make bunnyhopping possible.

CYNIC, n. A blackguard whose faulty vision sees things as they are, not as they ought to be. Hence the custom among the Scythians of plucking out a cynic’s eyes to improve his vision