- Fixed the set command for WinXP. 
- The second parameter must be zero in the call to SetEnvironmentVariable 
  if the variable should be deleted.

reactos/subsys/system/cmd

diff -u -r1.2 -r1.3
--- set.c	7 Aug 2003 09:27:42 -0000	1.2
+++ set.c	6 Jun 2004 09:03:07 -0000	1.3
@@ -94,7 +94,10 @@

 		/* set or remove environment variable */
 		*p = _T('\0');
 		p++;

-

+		if (*p == _T('\0'))
+		{
+			p = NULL;
+		}

 		SetEnvironmentVariable (param, p);
 	}
 	else