[Gtkradiant] help gtkradiant for OSX

[Mik]

Hello.

I need help for installing gtkradiant for Mac OSX 10.4.8 PPC G5 dual  
1.8.

I've got the GtkRadiant-GPL.zip file with the source code
but i have some errors when i do ./install.py

I got:


./install.py: line 27:
Builds the ./install directory.

Copies files from various locations:
./setup/data/tools/
./games/<gamepack>/
../<library>/<library>.dll
./include/version.default is used to generate RADIANT_MAJOR and  
RADIANT_MINOR
: No such file or directory
./install.py: line 29: import: command not found
./install.py: line 30: import: command not found
./install.py: line 32: syntax error near unexpected token `('
./install.py: line 32: `def assertMessage(condition, message):'



How to compile the source?

Please help me!

Regards

Mike