Change Users Variables - Delphi IDE

I am using an automated build tool called Automated Build 开发者_运维问答Studio.

I have defined in the Delphi IDE, as you can see in the screenshot, a user variable $(PLKFW) which points to a specific folder in my computer.

The question is:

How can I change this $(PLKFW) variable without using the delphi IDE?

The Environment Variables defined in the Delphi 2010 IDE are stored in this windows registry key

HKEY_CURRENT_USER\Software\CodeGear\BDS\7.0\Environment Variables

just remember be careful when you edit this kind of IDE setting externally (without use the delphi IDE).