The scheduled Event dates and time are working for the actual date selected, for example Friday the 27th May, but the OpenMeetings Calendar shows the 27th of May as being a Saturday which is an error.
The 27/04/2012 is actually a Friday in Australia (i.e. GMT+10) timezone, but shows in the calendar as being on the Satuday after the Friday.
Invitations and Reminders are not affected as they do not state a text "Day" or Month", but only give a numeric date, such as;
Start: 26.04.2012 14:15:00 EST (+1000)
End: 26.04.2012 23:55:00 EST (+1000)