How do I set focused borders around button widgets?

[Taura <learfox taura ccinet com>]

How do I set focuxed borders around the button widgets like
those on buttons within the file selector widget?

--
Sincerely,                  ,"-_                         \|/
-Taura                      ,   O=__                    --X--
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                  http://furry.ao.net/~learfox/