git-instaweb portability issue (maybe?)

Hi,

I'm on OS X 10.4.11 on Intel using git 1.5.5.3.

I'd been trying to use the git-instaweb script (both with and without
arguments) with lighttpd (which I installed through Macports) without
success, seeing the following kind of bizarre error message:

    funsat[290] > git instaweb
    /opt/local/bin/git-instaweb: line 6033: /usr/bin/env perl: No such
file or directory
    2008-06-13 09:09:31: (log.c.75) server started

    funsat[291] > 2008-06-13 09:09:31: (mod_cgi.c.998) CGI failed:
Exec format error /Volumes/work/funsat/.git/gitweb/gitweb.cgi
    mod_cgi.c.1001: aborted
    2008-06-13 09:09:31: (mod_cgi.c.584) cgi died, pid: 23237

"/usr/bin/env perl: No such file or directory"? Huh?  I certainly have
perl installed, so I don't know what that's about.

That line simply calls perl by the $PERL variable, which is set at the
top of the script, like so:

    PERL='/usr/bin/env perl'

If I change this line to point to my perl directly, it works.  On a
hunch, I changed it to:

    PERL="/usr/bin/env perl"  # note the double-quotes

And now it works.  Could this be changed for future releases of git?
Does this in fact increase portability, or is something more sinister
going on?

Thanks.

-- 
 Denis