I'm running Thunderbird 2.0.0.4 with Lightning 0.5RC2 and 20 or
so .ics calendar files served by WebDAV.
Thunderbird is sporadically unresponsive and also doesn't shut down
cleanly - I have to "End Process" from the Windows XP Task Manager.
Not sure if these factors are related or not but I thought I'd mention
them just in case.