Resource Mailbox Not Declining Conflicting Appointments

Question

Recently upgraded from Exchange 2003 to Exchange 2010.
All of my resource mailboxes are allowing conflicting meeting requests to be scheduled, even though in the window when you are scheduling it, it says "conflicts with another appointment".
Resource attendants are enabled, and the box for "allow conflicting meeting requests" is NOT checked. 
Maximum conflict instances is 0, and conflict percentage allowed is 0.
And I am not scheduling any recurring meetings.  If there is a meeting already schedule from 1-2 (for example) and I go on the calendar and schedule another meeting in the same resource from 12:30-2:00 it lets me schedule it, never declines it or anything.
I have looked around a bunch and can't seem to figure out what is wrong, so any assistance would be greatly appreciated.

Answer 1

Still banging my head against this.  Here are the settings for a mailbox that doesn't work (k2) and a mailbox that does (strategysummit).  The k2 mailbox is a mailbox that was created in exchange 2003 and then migrated to a resource mailbox during
the migration.  Strategysummit is a new room mailbox created after the migration and works fine.  All my room mailboxes created in 2003 are having this problem.
RunspaceId                          : aa671879-75ca-4961-a103-4dcd35254689
AutomateProcessing                  : AutoAccept
AllowConflicts                      : False
BookingWindowInDays                 : 180
MaximumDurationInMinutes            : 1440
AllowRecurringMeetings              : True
EnforceSchedulingHorizon            : True
ScheduleOnlyDuringWorkHours         : False
ConflictPercentageAllowed           : 0
MaximumConflictInstances            : 0
ForwardRequestsToDelegates          : True
DeleteAttachments                   : True
DeleteComments                      : True
RemovePrivateProperty               : True
DeleteSubject                       : True
AddOrganizerToSubject               : True
DeleteNonCalendarItems              : True
TentativePendingApproval            : True
EnableResponseDetails               : True
OrganizerInfo                       : True
ResourceDelegates                   : {}
RequestOutOfPolicy                  : {}
AllRequestOutOfPolicy               : False
BookInPolicy                        : {}
AllBookInPolicy                     : True
RequestInPolicy                     : {}
AllRequestInPolicy                  : False
AddAdditionalResponse               : False
AdditionalResponse                  :
RemoveOldMeetingMessages            : True
AddNewRequestsTentatively           : False
ProcessExternalMeetingMessages      : True
RemoveForwardedMeetingNotifications : False
MailboxOwnerId                      : offwire.com/Offwire Users/Exchange/Exchange Resources/Resource - K2
Identity                            : offwire.com/Offwire Users/Exchange/Exchange Resources/Resource - K2
IsValid                             : True
RunspaceId                          : aa671879-75ca-4961-a103-4dcd35254689
AutomateProcessing                  : AutoAccept
AllowConflicts                      : False
BookingWindowInDays                 : 180
MaximumDurationInMinutes            : 1440
AllowRecurringMeetings              : True
EnforceSchedulingHorizon            : True
ScheduleOnlyDuringWorkHours         : False
ConflictPercentageAllowed           : 0
MaximumConflictInstances            : 0
ForwardRequestsToDelegates          : True
DeleteAttachments                   : True
DeleteComments                      : True
RemovePrivateProperty               : True
DeleteSubject                       : True
AddOrganizerToSubject               : True
DeleteNonCalendarItems              : True
TentativePendingApproval            : True
EnableResponseDetails               : True
OrganizerInfo                       : True
ResourceDelegates                   : {}
RequestOutOfPolicy                  : {}
AllRequestOutOfPolicy               : False
BookInPolicy                        : {}
AllBookInPolicy                     : True
RequestInPolicy                     : {}
AllRequestInPolicy                  : False
AddAdditionalResponse               : False
AdditionalResponse                  :
RemoveOldMeetingMessages            : True
AddNewRequestsTentatively           : True
ProcessExternalMeetingMessages      : False
RemoveForwardedMeetingNotifications : False
MailboxOwnerId                      : offwire.com/Offwire Users/Exchange/Exchange Resources/Strategy Summit
Identity                            : offwire.com/Offwire Users/Exchange/Exchange Resources/Strategy Summit
IsValid                             : True