[CSS21] How to set width to a column-group element?

Hello,

Under which context or circumstances is it possible to set the width of a
column group element? I am looking for a test which would demonstrate
this, how it works, the logic of distributing width or calculating width
of sub-table elements.

It now seems certain to me that such table would not be resorting to table
layout fixed algorithm. But then, with table layout auto algorithm, I can
not figure this out either.

Here's the test I've been working on:

http://www.gtalbot.org/BrowserBugsSection/css21testsuite/width-applies-to-005-auto-GT.xht

I believe there is a flaw in CSS 2.1 spec, otherwise setting width to an
table-column-group is just not working or reliable.

Gérard
-- 
CSS 2.1 Test suite RC6, March 23rd 2011
http://test.csswg.org/suites/css2.1/20110323/html4/toc.html

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