> Does anybody already ported the native code compiler for ocaml-2.0x to
> R4000?

there is a series of workstations from NEC, EWS4800, with mips R4000 cpu.
I believe Cenju-4 and EWS4800 use totally different OSes, so,
this message is not so interesting for wakita san, but here goes...

I compiled (a part of) ocaml-2.02 on EWS4800.
I can build the bytecode system successfully, but
compilation of the native code system failed.
I suppose the #ifdef code around signal handling should be modified a little.
(and I don't know how many other problems remain.) 

I logged the compilation process using script command.  see 
  <http://aohakobe.ipc.chiba-u.ac.jp/misc/docs/ocaml/ews4800/>
  <ftp://aohakobe.ipc.chiba-u.ac.jp/misc/docs/ocaml/ews4800/>
if you're interested.

-- yozo.