In case you didn't see this in linux-kernel. I don't know
if RH 5.2 is affected:
(BTW, bugzilla doesn't have net-tools in the list of
packages)

From: olaf.de (Olaf Titz)
Newsgroups: lists.linux.kernel
Subject: Re: [2.0.36] proxy ARP prob?
Date: 13 Dec 1998 08:40:04 -0800
Organization: private Linux site, southern Germany

> Hopefully somebody can point out what I'm doing something
wrong here.
> I'm trying to put a permanent entry into the ARP cache for
a network,
> on interface eth1.  For some reason it really likes eth0
instead.

Red Hat's arp binary is broken, because of the $@{%*#!'"
glibc
compatibility problems. I discovered that the hard way
recently. Get
the net-tools source and remove the ifdefs around the
defines of
HAVE_NEW_SIOCSARP, HAVE_NEW_ADDRT, HAVE_RTF_IRTT,
HAVE_RTF_REJECT in
lib/net.-features.h. (The newest net-tools apparently does
arp right
out of the box but its netstat seems to be broken. Sigh.)

Olaf