The i-net has failed me once again!!

I tried to find some registry fix for this problem but google has failed me..
I am not using any drivers for my razer diamondback, however I have fixed my registry for no accelaration and now I want to change 1 more thing....
Basic layout of mousebuttons on the razer:

this is a pic from the razer drivers but the windows standard driver layout is the same, mouse button 4 @ leftside front and mouse button 5 @ rightside front... but since I only use the leftside I would like to change this (also because ET only binds up to mouse5) so that I have 4 and 5 on the leftside..
Razer drivers sux because of the accel issues etc.

btw tried to hax it myself but I failed.

Plse PM me if you have any idea + for more info's if u want to help me out.
Or just comment if you are sure I cant fix it this way.

Another challenge for nC... hax my mouse (won't give you any money though.) xD