jhbuild bootstrap: "LookupError: unknown encoding: "

I must have missed something, but I'm running into a python error that confuses me. The full log of what I did is shown below. I'm guessing it has something to do with locale settings I have on my Leopard machine, but I just don't know which one. Looking at the following, can anybody tell me what's wrong?

philip-holzenspiess-macbook:~ holzensp$ gtk-osx-build-setup.sh
Checking out jhbuild from subversion...
Installing jhbuild...
Installing jhbuild configuration...
Done.
philip-holzenspiess-macbook:~ holzensp$ ls bin/
gtk-osx-build-setup.sh install-check jhbuild
philip-holzenspiess-macbook:~ holzensp$ jhbuild bootstrap
Prefix: /Users/holzensp/gtk/inst
Traceback (most recent call last):
File "/Users/holzensp/bin/jhbuild", line 6, in
jhbuild.main.main(sys.argv[1:])
File "/Users/holzensp/Source/jhbuild/jhbuild/main.py", line 113, in main
rc = jhbuild.commands.run(command, config, args)
File "/Users/holzensp/Source/jhbuild/jhbuild/commands/__init__.py", line 78, in run
return cmd.execute(config, args)
File "/Users/holzensp/Source/jhbuild/jhbuild/commands/__init__.py", line 44, in execute
return self.run(config, options, args)
File "/Users/holzensp/Source/jhbuild/jhbuild/commands/bootstrap.py", line 38, in run
return cmd_build.run(self, config, options, args)
File "/Users/holzensp/Source/jhbuild/jhbuild/commands/base.py", line 228, in run
return build.build()
File "/Users/holzensp/Source/jhbuild/jhbuild/frontends/buildscript.py", line 102, in build
nextstate, error, altstates = module.run_state(self, state)
File "/Users/holzensp/Source/jhbuild/jhbuild/modtypes/__init__.py", line 178, in run_state
method(buildscript)
File "/Users/holzensp/Source/jhbuild/jhbuild/modtypes/autotools.py", line 89, in do_checkout
self.checkout(buildscript)
File "/Users/holzensp/Source/jhbuild/jhbuild/modtypes/__init__.py", line 213, in checkout
buildscript.set_action(_('Checking out'), self)
File "/Users/holzensp/Source/jhbuild/jhbuild/frontends/terminal.py", line 108, in set_action
self.message('%s %s' % (action, action_target), module_num)
File "/Users/holzensp/Source/jhbuild/jhbuild/frontends/terminal.py", line 92, in message
uprint('%s*** %s ***%s%s' % (t_bold, msg, progress, t_reset))
File "/Users/holzensp/Source/jhbuild/jhbuild/main.py", line 48, in uprint
print s.encode(_encoding, 'replace')
LookupError: unknown encoding:
philip-holzenspiess-macbook:~ holzensp$

I'm at a loss. Thanks in advance for any suggestions.