I could not resist digging into my administrative and shell experience when I saw that somebody wrote a php script to dynamically split lighttpd logs. Hmm I use php for more complicated stuff.
I achieved this by putting the following into lighttpd.conf
accesslog.filename = "|/usr/bin/splitlog.sh"
The following is the listing for splitlog.sh, shell veterans, please comment if I am overdoing this. Since my exposure is of very low.
#!/bin/bash logDir="/var/log/lighttpd" cat - | while read line do dom=$(echo $line | cut -f2 -d" ") echo $line >> $logDir/${dom}-access.log done