#!/bin/sh is interpreted inconsistently across platforms.  In the rpm
world it most often maps to /bin/bash.  In the Debian universe it maps
to /bin/dash.  Bash and dash have subtle differences that have bitten
me often enough to cause me now to use precise shebangs (#!/bin/bash or
#!/bin/dash) and to suffix my files with either .bsh or .dsh.

At present emacs' interpreter-mode-alist knows nothing about dash and
its auto-mode-alist is ignorant of both the .bsh and .dsh suffixes.

For interpreter-mode-alist I suggest adding the follow entry:

     ("dash" . sh-mode)


For auto-mode-alist I suggest changing the follow entry:

     ("\\.[ck]?sh\\'\\|\\.shar\\'\\|/\\.z?profile\\'" . sh-mode)

to

     ("\\.[bcdk]?sh\\'\\|\\.shar\\'\\|/\\.z?profile\\'" . sh-mode)

/john