.htaccess not working (Apache Users)

I've taken the following .htaccess from CentOS 4.5 with Apache 2

Options +FollowSymLinks

RewriteEngine on
RewriteRule ^([0-9]+) index.php?forum_id=$1&%{QUERY_STRING}

which works fine, however when putting it onto an old RHEL3/Apache 2 machine that we've got to use for development it just 404s and the only log generated is:

10.10.100.43 - - [21/Aug/2007:11:48:10 +0100] "GET /help/forum/forum/1/ HTTP/1.1" 404 307 "http://www.bc.minke/help/forum/" "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.8.1.6) Gecko/20070725 Firefox/2.0.0.6"

From documentation, google and comparing config with the CentOS machine I believe all I need in the .conf files is

LoadModule rewrite_module modules/mod_rewrite.so (this file does exist and I even tried restarting apache with mod_rewrite.so from the CentOS machine, just incase it worked)

however it would seem that I'm wrong.

I've also checked permissions, which I think are ok.

-rwxrwxr-x 1 root apache 105 Mar 16 16:54 .htaccess
-rwxrwxr-x 1 root apache 838 Mar 29 16:12 index.php
drwxrwxr-x 2 root apache 4096 Mar 20 15:39 topic

-rwxrwxr-x    1 peter.davies rrweb         105 Mar 16 19:07 .htaccess
-rwxrwxr-x    1 peter.davies rrweb         838 Mar 29 17:56 index.php
drwxrwxr-x    2 peter.davies rrweb        4096 Mar 6 16:55 topic

Perhaps someone could point me in the right direction to working out what I've missed?

--

John Clement | System Administrator | Reading Room Ltd
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