Phone randomly restarted is something I've exprienced myself and have read is bothering others as well. But the calendar issue is new to me.
Really hope they release 4.0.3 and higher quickly.
I've not experienced any other reset/lock in the last week or so. I guess it's pretty much random. The calendar is also working fine as far as I can tell.
I also hope they'll release an update ASAP.