I've reviewed this to double check that this isn't my working environment (browser). I have not yet ruled this out of my install (wre7.2-ubuntu 6.06). I am also attempting to install 7.4.3-beta to see if it is happening there as well. It may well be stupid operator error...
Posting an event to the calendar system will for unknown reasons sometimes post the event to the correct date, but more often than not, it posts it to the day before. I have verified that an event is posted as an all day event, and the time options disappear from the page. Yet, on save and return to the calendar event review page, it shows a time range.
I have been able to duplicate this on Firefox and IE6. I have seen "view-window" issues in the past where the slide bar interacts with dynamic content and misplacement of form data occurs on various browsers. I don't believe this is such an instance.
Stephen Opal
This is what I did:
Create a new demo site.
Login to admin account
Create calendar on home page (appears at bottom)
Commit the calendar
With August as default month, Add Event for "Stephen' Birthday" for all day September 2nd.
Save.
Navigate to September and see that it is posted on Sept 2nd (correctly).
Add Event for September 12th, named 'bbb' (leave as all-day event)
Save
Navigate to home page.
Click September month view.
September 12th event is now listed as September 11th with a time range of 7 PM to 8 PM.