Availability of cross-tools for Linux<-->OpenBSD?

[Michael Crogan <mcrogan_(_at_)_kc_(_dot_)_trail_(_dot_)_com>]

Hello.  Under Linux I would like to compile for OpenBSD.  However,
I cannot get either egcs-1.1.2 (patched or not), egcs-19990616 or
any version of gcc to work as a cross compiler for OpenBSD from Linux
(kernel 2.2.5-22; distribution RedHat 6.0).  I copy the latest snapshot
libraries and headers from the FTP site, and set the destination properly,
but I have not yet found a version which actually compiles.  Each version
I have tried gives too many errors to count.  Has anyone successfully
cross-compiled from Linux?

Secondly, is much involved in building Linux binaries from OpenBSD source?
After enough modification to the /usr/share/mk files (and after porting
bmake), would it be possible to build most of the BSD tools under /usr/src
for Linux?

Any information would be helpful.  Thanks in advance.

Mike