Ok, this is pretty frustrating. I do know that on 10.6 I have bash.
$ echo $SHELL
/bin/bash
Now, when I look at my .bashrc file at /Users/<username>, I have this fun:
$ cat .bashrc
alias l='ls'
alias la='ls -a'
alias ll='ls -l'
alias lla='ls -la'
In theory, all should be well...