Set it up like you were using a custom Makefile project. You'll have to write the SConstruct file yourself, but it is relatively easy. The SConstruct file should be located in the project root (where the .cpb file is located).
On the Projects/targets opitions dialog check the This is a custom Makefile box and enter the SConstruct file name which typically is "SConstruct".
Then on the Project build options dialog, click on the "Make" commands tab and change:
Build project/target: to "c:\python23\scons.bat"
(I've skipped the compile single file...)
Clean project/target: to "c:\python23\scons.bat -c"
Dist-clean project/target: to "c:\python23\scons.bat"
I've assumed Windows, but pointing to scons should be all it should take to get it to work on other platforms.
This isn't a "fully integrated" solution, but should at least make scons projects usable.