It's an issue with ActivePython, not Visual Build, so it's not something we can fix. ActiveState needs to fix the Active Scripting support, or you'll have to keep using an older version of ActivePython that doesn't have this problem.
We already provided this to ActiveState last year, but here is a test program that demonstrates the problem, in case you would like to send it to them again:
http://www.kinook.com/Download/Temp/PyTest.zip