Hi,
It'd be great if we have some abstract and pure (no C/assembly inline) language to write dissectors.
We could invent yet another protocol desciption language, but I was thinking
to base grammar on netmon NPL [1] or wsgd [2].
I'm bigger fan of NPL (sorry Olivier), nmparsers project has got large collection of dissectors[3]
which we could use (LLTD - bug #6071, Windows USB Port packets - bug #6520, netsh - bug #6694)
but there might exists some legal (patents for grammar/implementation?!) issues.
With wsgd we could reuse some existing code of plugin.
[1] http://blogs.technet.com/b/netmon/archive/2006/10/04/npl-_1320_-the-power-behind-the-parsers.aspx
[2] http://wsgd.free.fr/first_proto.html
[3] http://nmparsers.codeplex.com/