C++ interface build on FreeBSD 4.2 broken?

It is reported that building C++ interface on FreeBSD 4.2 fails.
Can someone comment on this?

c++ -pipe -O3 -mpentiumpro -Wall -fpic -DPIC -I/usr/local/ssl/include
-I../../../src/include -I../../../src/interfaces/libpq -c -o pgconnec
tion.o pgconnection.cc
In file included from ../../../src/include/postgres.h:40,
from pgconnection.h:41,
from pgconnection.cc:18:
../../../src/include/c.h:997: conflicting types for `int sys_nerr'
/usr/include/stdio.h:224: previous declaration as `const int sys_nerr'
gmake[3]: *** [pgconnection.o] Error 1
gmake[3]: Leaving directory `/home/ichimura/Work/postgresql-snapshot/s
rc/interfaces/libpq++'
gmake[2]: *** [all] Error 2
gmake[2]: Leaving directory `/home/ichimura/Work/postgresql-snapshot/s
rc/interfaces'
gmake[1]: *** [all] Error 2
gmake[1]: Leaving directory `/home/ichimura/Work/postgresql-snapshot/s
rc'
gmake: *** [all] Error 2