When I specify sort fields via the datasource.sort() option, the result is different in Chrome than it is in IE.
In IE, multiple all-day events in the same day appear sorted correctly on the calendar. In chrome, the same events render *slightly* out of order.
In both browsers, printing that set of events to the console reveals that the datasource itself is sorted correctly in both browsers, but it appears the calendar control does not render them in the specified order, in Chrome.
I've included screenshots of my data in Chrome...
1) my sort configuration
2) the day's data, sorted, printed to the console
3) the day's data, sorted, rendered on the calendar