#! comment !# for scheme?

I'm trying to make `scheme.el' cause #! comments !# to work, akin to the Common Lisp #| comments |#, but cannot get it to work. I'm very frustrated trying; I've copied it straight from `lisp-mode.el': (modify-syntax-entry ?# "' 58" scheme-mode-syntax-table) (modify-syntax-entry ?\! "_ 67" scheme-mode-syntax-table) ... but still when I visit a scheme file with: #!/usr/bin/guile -s !# ... at the top, that section is not highlighted by font-lock as a comment like it should. I know this isn't really a very important thing to do... but it should work, shouldn't it? What's wrong?