postflight.framework fails during installation:

. . .
Sep 17 17:36:53 mcfro Installer[1613]: run postflight script for Python 
Framework
Sep 17 17:36:53 mcfro runner[1633]: postflight[1660]: /Volumes/Python 
3.1.1/Python.mpkg/Contents/Packages/PythonFramework-
3.1.pkg/Contents/Resources/postflight: line 9: 
/Library/Frameworks/Python.framework/Versions/3.1/bin/python: No such 
file or directory
Sep 17 17:36:53 mcfro runner[1633]: postflight[1660]: 
Sep 17 17:36:53 mcfro runner[1633]: postflight[1660]: /Volumes/Python 
3.1.1/Python.mpkg/Contents/Packages/PythonFramework-
3.1.pkg/Contents/Resources/postflight: line 14: 
/Library/Frameworks/Python.framework/Versions/3.1/bin/python: No such 
file or directory
Sep 17 17:36:53 mcfro runner[1633]: postflight[1660]: /Volumes/Python 
3.1.1/Python.mpkg/Contents/Packages/PythonFramework-
3.1.pkg/Contents/Resources/postflight: line 19: 
/Library/Frameworks/Python.framework/Versions/3.1/bin/python: No such 
file or directory
Sep 17 17:36:53 mcfro runner[1633]: postflight[1660]: 
Sep 17 17:36:53 mcfro runner[1633]: postflight[1660]: /Volumes/Python 
3.1.1/Python.mpkg/Contents/Packages/PythonFramework-
3.1.pkg/Contents/Resources/postflight: line 24: 
/Library/Frameworks/Python.framework/Versions/3.1/bin/python: No such 
file or directory
Sep 17 17:36:53 mcfro runner[1633]: postflight[1660]: 
Sep 17 17:36:53 mcfro runner[1633]: postflight[1660]: chown: admin: 
Invalid argument
Sep 17 17:36:53 mcfro runner[1633]: postflight[1660]: 

The first problem is that in 
/Library/Frameworks/Python.framework/Versions/3.1/bin there is no 
executable 'python' anymore - there is 'python3.1', etc.

Also chown at the end should set the group to 'admin', not the owner.

I've attached a patch that fixes these issues. (the problem with chown 
is also present in the installer for 2.6.x ).