Comment 2 for bug 498623

I believe that the following calls are o.k., since they are either done for an empty buffer, or immediately followed by a call to erase-buffer:
   vm-edit.el:73: (set-buffer-multibyte nil))
   vm-mime.el:2733: (set-buffer-multibyte nil))
   vm-mime.el:3112: (set-buffer-multibyte nil))
   vm-mime.el:5237: (set-buffer-multibyte nil))
   vm-pine.el:1154: (set-buffer-multibyte nil))
   vm-window.el:126: (set-buffer-multibyte nil))
   vm-window.el:145: (set-buffer-multibyte nil))

The following is redundant and should be removed (vm-make-work-buffer is guaranteed to create a single-byte buffer):
   vm-mime.el:4609: (set-buffer-multibyte nil))

Still to be checked:
   vm.el:134: (set-buffer-multibyte nil))
   vm-mime.el:321: (and vm-fsfemacs-p (set-buffer-multibyte t))
   vm-mime.el:1956: (and vm-fsfemacs-mule-p (set-buffer-multibyte t))
   vm-reply.el:980: (set-buffer-multibyte t)))
   vm-save.el:65: (set-buffer-multibyte nil))