Version:           4.5.5 (using KDE 4.5.5) 
OS:                Linux

If 2 collapsing borders have the same 'border-width', then 'ridge' border-style wins over 'outset' border-style.

3 testcases:

a) 
http://test.csswg.org/suites/css2.1/20110111/html4/border-conflict-style-079.htm

b) 
http://test.csswg.org/suites/css2.1/20110111/html4/border-conflict-style-088.htm

c) 
http://www.gtalbot.org/BrowserBugsSection/Konqueror4Bugs/ridge-wins-over-outset.html

CSS 2.1, section 17.6.2.1 Border conflict resolution states

"
If several have the same 'border-width' then styles are preferred in this order: 'double', 'solid', 'dashed', 'dotted', 'ridge', 'outset', 'groove', and the lowest: 'inset'.
"
http://www.w3.org/TR/CSS21/tables.html#border-conflict-resolution

Reproducible: Always

Steps to Reproduce:
Load 3 provided testcases

Actual Results:  
There is a red outset border in all 3 testcases

Expected Results:  
There should be a green ridge border in all 3 testcases.

Linux 2.6.35-24-generic-pae, i686 (32bits), Qt 4.7.0, Konqueror 4.5.5 here.