It looks like this error's coming from the Calendar JS rather than the scheduler JS.
if($02.firstChild&&$02.firstChild.firstChild&&$02.firstChild.firstChild.tagName.toUpperCase()=='IMG')
I have two calendars and a scheduler attached to a navigator. The "TimeRangeSelectedJavaScript" for the navigator calls commandCallBack("navigate", {start:start}) on all three controls. The scheduler updates, but the calendars don't.