Incorrect font shorthands (e.g., font: Arial) pass validation

I noticed that
   font: Arial normal
passes validation. Then I checked
   font: Arial
and it passes, too.

This is serious because in addition to being incorrect by the specs, 
these declarations fail to do what they are intended to do. And it is 
fairly common to err here, omitting the required font size value.

-- 
Yucca, http://www.cs.tut.fi/~jkorpela/