getClientRects result in IE versus Mozilla

I am confused as to what getClientRects() called on an element object 
returns in Mozilla. For IE, as far as I understand it, it returns a 
collection of TextRectangle objects, one for each rendered line of text 
in the element. For Mozilla I always get a collection of one rectangle.

Test case is here:
http://home.arcor.de/martin.honnen/javascript/2008/08/test2008082301.html

For IE 6 the output is

'P' element has 3 line(s).

'P' element has 4 line(s).

'UL' element has 3 line(s).

(where the result for the first 'P' element obviously depends on the 
browser window width).

For Mozilla the output however is

'P' element has 1 line(s).

'P' element has 1 line(s).

'UL' element has 1 line(s).

Tested with Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.1) 
Gecko/2008070208 Firefox/3.0.1

The documentation at 
http://developer.mozilla.org/en/DOM/element.getClientRects also has a 
code example saying

   var rects = obj.getClientRects();
   var numLines = rects.length;

which with numLines suggests there should be a rectangle for each line 
of text.

Is the result Mozilla gives the intended result? How would the markup 
look for an element where getClientRects() in Mozilla would return a 
collection with more than one rectangle?



-- 

	Martin Honnen
	http://JavaScript.FAQTs.com/