It would be nice if jEdit could support Emacs mode strings for mode settings. A simple addition would be to include mode strings in the default first line globs. For example, to detect non-executable Perl files which have no extension but whose first line starts with a shebang or "# -*- mode: perl; -*-":
A more difficult feature would be the support for overrides of the jEdit mode settings with strings like this:
; -*- mode: Lisp; tab-width: 4; -*-
This could make it easier to share files, especially since there is (AFAIK) no way to specify mode settings per directory tree.