OK, let's hope for the best ;)

I'm afraid I don't have access to the computer this occurred on anymore.
However, I think we can close this one without verifying it on that machine - I 
trust your string parsing abilities.

Thanks for bringing this to my attention. I fixed this in master. Can you confirm 
this, please?

The labs package does not parse python 2.7.2+ version correctly:

tal@ubuntu:~/lab$ python ihc.py 1
2012-06-10 15:08:31,884 INFO     Running build-preprocess-exp:
build(stage='preprocess')
2012-06-10 15:08:31,884 INFO     Running command: ./build_all {'cwd':
'/home/tal/downward-bgu/src'}
make: Nothing to be done for `default'.
make: Nothing to be done for `default'.
make: Nothing to be done for `default'.
make: Nothing to be done for `default'.
make: `validate' is up to date.
2012-06-10 15:08:32,117 INFO     Requiring /home/tal/downward-bgu/src
2012-06-10 15:08:32,120 INFO     Python version: 2.7.2+
Traceback (most recent call last):
  File "/home/tal/lab/lab/steps.py", line 48, in __call__
    retval = self.func(*self.args, **self.kwargs)
  File "/home/tal/lab/downward/experiment.py", line 373, in build
    self._check_python_version()
  File "/home/tal/lab/downward/experiment.py", line 332, in _check_python_version
    version = [int(part) for part in version.split('.')]
ValueError: invalid literal for int() with base 10: '2+'
2012-06-10 15:08:32,121 CRITICAL Could not run step: build(stage='preprocess')
aborting