etags licence?

[Ulrich Mueller]

I just discovered that the etags.c included with Emacs 22 is now
dual-licenced BSD/GPL, while up to Emacs 21.4 it was GPL only.

As a consequence, this would mean that Gentoo has to mark its Emacs
packages with "GPL-3 FDL-1.2 BSD" as licence info.

Some quick web search reveals that the ctags source was posted at
least two times to net.sources and mod.sources in 1984/85, without any
copyright statement. (This version clearly shows similarities to the
etc/etags.c included in Emacs 16.56.)

I also found a posting by Ken Arnold from 1985 that states "The source
to ctags is public domain":
<http://groups.google.de/group/net.unix-wizards/browse_thread/thread/43a6b9daae705a7e/785d2b69b9ac7d6f?lnk=st&q=ctags&rnum=7&hl=de#785d2b69b9ac7d6f>

So I wonder if the BSD licensing for etags is correct?

Ulrich