Is it possible for Thunderbird-Lightning to delete a calendar on a webDAV server???

[Kevin J. Cummings]

My /var/www/html/dav/Home.ics file disappeared yesterday (just before
noon) from my home server (F13.i686).  My laptop (F14.x86_64) was online
at a remote location at the time, and thunderbird was open, and I was
reading emails via dovecot.  I found the following entries in my
server's httpd/access_log:

> www.203.238.22 - - [28/Dec/2010:11:56:23 -0500] "GET /dav/Home.ics HTTP/1.1" 200 112440 "-" "Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101209 Fedora/3.1.7-0.35.b3pre.fc14 Lightning/1.0b3pre Thunderbird/3.1.7"
> www.203.238.22 - - [28/Dec/2010:11:56:25 -0500] "PUT /dav/Home.ics HTTP/1.1" 401 485 "-" "Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101209 Fedora/3.1.7-0.35.b3pre.fc14 Lightning/1.0b3pre Thunderbird/3.1.7"
> www.203.238.22 - cummings [28/Dec/2010:11:57:32 -0500] "PUT /dav/Home.ics HTTP/1.1" 500 632 "-" "Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101209 Fedora/3.1.7-0.35.b3pre.fc14 Lightning/1.0b3pre Thunderbird/3.1.7"

This was within seconds of un-suspending my laptop from the
suspend-to-RAM state (after it had connected to one of the local WiFi
connections).

And if I look at the /var/www/html/dav directory on my server:

> # ls -latr
> total 48
> -rw-r--r--.  1 root   root   12224 Sep 25  2009 home.ics.saved
> -rw-r--r--.  1 root   root   12177 Sep 25  2009 Home.ics~
> drwxr-xr-x.  2 apache apache  4096 Dec 28 11:59 .
> drwxr-xr-x. 24 root   root    4096 Dec 29 00:12 ..

It looks to me like my calendar disappeared just before noontime....
(the other files there are from the last time webDAV screwed up on me,
but at that time, 15 months ago, it was only a partial corruption of my
file.)

I didn't (intentionally) do it!  How could it have disappeared?
What happened to my Home.ics calendar????  Is there somewhere's
else I can look for clues?

I didn't even notice this until just before midnight last night!

I have logs showing that it was working fine the day before....

-- 
Kevin J. Cummings
kjchome at rcn.com
cummings at kjchome.homeip.net
cummings at kjc386.framingham.ma.us
Registered Linux User #1232 (http://counter.li.org)