We are getting intermittent build failures of the following form:

BUILD FAILED
C:\workspace\2.1-graphics-smoketest\label\windows-i586-14\build-src\build-components.xml:334: The following error occurred while executing this line:
C:\workspace\2.1-graphics-smoketest\label\windows-i586-14\build-src\build-components.xml:219: The following error occurred while executing this line:
C:\workspace\2.1-graphics-smoketest\label\windows-i586-14\build\xml_generated\build-glass.xml:57: The following error occurred while executing this line:
C:\workspace\2.1-graphics-smoketest\label\windows-i586-14\build-src\build-components.xml:75: The following error occurred while executing this line:
C:\workspace\2.1-graphics-smoketest\label\windows-i586-14\glass\build.xml:128: The following error occurred while executing this line:
C:\workspace\2.1-graphics-smoketest\label\windows-i586-14\glass\build.xml:50: The following error occurred while executing this line:
C:\workspace\2.1-graphics-smoketest\label\windows-i586-14\glass\build.xml:43: The following error occurred while executing this line:
C:\workspace\2.1-graphics-smoketest\label\windows-i586-14\glass\glass-mat-lib-windows\build.xml:61: The following error occurred while executing this line:
C:\workspace\2.1-graphics-smoketest\label\windows-i586-14\build-src\build-windows-defs.xml:228: The following error occurred while executing this line:
C:\workspace\2.1-graphics-smoketest\label\windows-i586-14\build-defs.xml:153: ERROR: File check failed, missing: c:\Program Files\Microsoft Visual Studio 10.0\VC\@@ENDOFLThe system cannot find the path specified.\bin\cl.exe

See: http://jfx.us.oracle.com/hudson/job/2.1-graphics-smoketest/label=windows-i586-14/90/console

The problem is in the generation of the build/vs.properties file (attached).