Just updated Leopard and now having "#!/bin/sh" in the "command(s)" section of the bundle editor for any bundle yields "bad interpreter: no such file or directory" if I remove the directive, it works fine, but now on the shell bundle, the run command script is a ruby script and TextMate will not take #!/usr/bin/env ruby, yields bad interpreter again, but I really need to tell TextMate this is a ruby script. So I ran the script with ruby -e'do something'. That is weak sauce but it works. I also noticed circular dependencies in the bundles. You need ruby to run a python script in the python bundle; you need bash to run a ruby script, you need ruby to run a shell script.
I am not sure why this is because the text in command(s) should be treated as a shell script. Anyway, if anyone else has this problem, then removing the shell directive line should help.