"Fallback" alias/function in zsh

[Paul Moore <gustav@xxxxxxxxxxxxxxxxxxxx>]

Hi,
Is it possible to define a function which gets used whenever zsh's
normal alias/function/builtin/path lookup fails? The best example I can
give of what I'm after is using zsh for Win32 (which is version 3.0.5).
There, I'd like to have access to the good old CMD.EXE builtins, like
DIR (at the moment, I don't have a working Unix-like ls). So, I thought,
how about defining a function to be called "when all else fails" which
does "CMD /C <the command I typed>"? But I couldn't find a way of doing
this.

Is it possible, or if not, would it be a useful addition?

Paul Moore