cat <<EOF>redirect.map
192.168.1. -
192.168.5. -
10.1. -
EOF

RewriteEngine on
RewriteMap ipmap dbm:/path/to/redirect.map
RewriteCond ${ipmap:%{REMOTE_ADDR}¦no-redir} ^-$
RewriteRule ^/(.*) http://www.example.com/$1 [L,R=301]