Sorry, but I've never used lighttpd so I can't really help.
One thing that looks suspicious is that you have a great big 'DAV on' in the middle of the config above.
I know that on Apache the most regular conflict for DAViCal is when someone accidentally enables mod_dav on the vague belief that "DAViCal must use mod_dav, right?" (it doesn't: DAViCal does all of the DAV stuff internally).
So quite possibly that is your problem right there.
Please post something about your success (or perhaps your failure) to the DAViCal Wiki and / or to the mailing list.
lighttpd setup
Sorry, but I've never used lighttpd so I can't really help.
One thing that looks suspicious is that you have a great big 'DAV on' in the middle of the config above.
I know that on Apache the most regular conflict for DAViCal is when someone accidentally enables mod_dav on the vague belief that "DAViCal must use mod_dav, right?" (it doesn't: DAViCal does all of the DAV stuff internally).
So quite possibly that is your problem right there.
Please post something about your success (or perhaps your failure) to the DAViCal Wiki and / or to the mailing list.
Regards,
Andrew McMillan.