All free/busy requests get error 403 in iCal with MobileMe

I'm playing for the first time with looking with my availability in iCal / Lion / MobileMe CalDAV accounts.

Everything else is working well with my calendars and Mobile Me.

I can add events, remove them, edit them, the sync is working well between the web interface and iCal on my Mac (10.7)

The only thing amiss is the availability window just logs an error to the console after a short time out.

It's error 403 which seems to be a permission denied error.

Do I need to grant permission for MobileMe to publish my free/busy status anywhere?

It it locked down until I allow sharing?

Is it tied to sharing a calendar some how?

Just sending a call out to others in case I'm missing something obvious. There are instances of this error on the boards with iCal and 10.6.6. so I presume it's more a server setup / service interruption than something I can change.

Thanks for any input - even if it's a "it works for me right now" or "I too can't get mobile me status in iCal"

(p.s. Mobile Me support says they can't help - talk with iCal people.)

(p.s. After two hours on the phone with iCal - it's back to the MobileMe people to try again. I figured I'd give a shout here before I try them again...)

Here's the error message from /private/var/log/system.log

7/27/11 12:48:30.780 PM          iCal          Error Error Domain=CoreDAVHTTPStatusErrorDomain Code=403 "The operation couldn’t be completed. (CoreDAVHTTPStatusErrorDomain error 403.)" UserInfo=0x7fd30cbbe3d0 {CoreDAVHTTPHeaders=<CFBasicHash 0x10300c1e0 [0x7fff7dbf7ea0]>{type = immutable dict, count = 7,
entries =>
          0 : <CFString 0x7fff7c240c18 [0x7fff7dbf7ea0]>{contents = "Server"} = <CFString 0x7fd30cabf370 [0x7fff7dbf7ea0]>{contents = "MobileMeCalendarServer 1C97"}
          2 : <CFString 0x7fd30cd8acb0 [0x7fff7dbf7ea0]>{contents = "DAV"} = <CFString 0x7fd30cb97840 [0x7fff7dbf7ea0]>{contents = "1, access-control, calendar-access, calendar-schedule, calendar-auto-schedule, calendarserver-sharing, calendarserver-subscribed, calendarserver-principal-property-search"}
          3 : <CFString 0x7fff7c240780 [0x7fff7dbf7ea0]>{contents = "Content-Type"} = <CFString 0x7fff7dbf1640 [0x7fff7dbf7ea0]>{contents = "text/xml"}
          4 : <CFString 0x7fff7c2407b8 [0x7fff7dbf7ea0]>{contents = "Date"} = <CFString 0x7fd30cbd9810 [0x7fff7dbf7ea0]>{contents = "Wed, 27 Jul 2011 17:48:30 GMT"}
          6 : <CFString 0x7fff7c240710 [0x7fff7dbf7ea0]>{contents = "Content-Length"} = <CFString 0x7fff7dbebe80 [0x7fff7dbf7ea0]>{contents = "280"}
          8 : <CFString 0x7fd30cd636e0 [0x7fff7dbf7ea0]>{contents = "X-Transaction-Id"} = <CFString 0x7fd30cbd7060 [0x7fff7dbf7ea0]>{contents = "nk11r10me-calsvr003-10-1311293226-3551930"}
          9 : <CFString 0x7fd30cab2b10 [0x7fff7dbf7ea0]>{contents = "X-Responding-Server"} = <CFString 0x7fd30cdeda10 [0x7fff7dbf7ea0]>{contents = "nk11r10me-calsvr003 10"}
}
} getting free-busy information for (
    "mailto:XXXXX@mac.com",
    "mailto:YYYYY@gmail.com"
)