to edit the right config file, you can find out what config file the current lighttpd process is using by:

ps uax|grep light
 1040 root 4212 S /usr/sbin/lighttpd -f /etc/lighttpd/lighttpd.conf

hope this helped
ps: i love lighttpd for beeing 1. light 2. quiet easy to config, less hacking like apache.

i love open source, but what do you think about apache products:

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