#!/bin/bash

logpath=/var/log
loglines=5000

for name in `ls $logpath`
do
tail -n $loglines $logpath/$name > /tmp/log.temp
cp -f /tmp/log.temp $logpath/$name
done
rm -f /tmp/log.temp

/bin/sleep 3
/usr/bin/killall -9 httpd
/bin/rm -rf /usr/local/apache/logs/*
/bin/sleep 5
/etc/rc.d/init.d/httpd startssl

==================================
Save it as trimvarlog
chmod to 700