Shebang line problems and python

[Blaine]

Hello,

Scripts that have "#!/usr/bin/python" at the top do not parse
correctly. Bash treats scripts with that shebang as if they are bash
scripts.

E.g.:
blaine at attila ~/apps/rs-mu $ /usr/sbin/env-update
/usr/sbin/env-update: line 6: import: command not found
/usr/sbin/env-update: line 8: syntax error near unexpected token `('
/usr/sbin/env-update: line 8: `def usage(status):'

Scripts with "#!/usr/bin/env python" at the top work fine. In fact,
`python` and `env python` both bring me to a python interpreter.

I've tried other types of scripts. #!/bin/bash works, #!/usr/bin/perl
works, #!/usr/bin/ruby works, etc. (and so do their #!/usr/bin/env
<interpreter> counterparts.) Because of this, I'm not sure if it is a
Python issue or a system issue.

Any and all advice appreciated, thanks.

P.S. some system info:
blaine at attila ~/apps/rs-mu $ uname -a
Linux attila 2.6.27-gentoo #5 SMP Sun Oct 19 19:13:17 MST 2008 i686
AMD Athlon(tm) 64 X2 Dual Core Processor 4000+ AuthenticAMD GNU/Linux

blaine at attila ~/apps/rs-mu $ python --version
Python 2.6.2

blaine at attila ~/apps/rs-mu $ bash --version
GNU bash, version 4.0.28(2)-release (i686-pc-linux-gnu)
Copyright (C) 2009 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/
gpl.html>