Parsing list-style shorthand property

A thread in alt.html[1] began due to the perceived inability of Opera to  
parse a list-style rule of the form:

   list-style: <type> none;

where <type> is a valid value other than none. In such an instance, it  
appears that Opera treats this rule as erroneous and ignores it entirely.

During a subsequent discussion on opera.page-display[2], it was asserted  
that such a declaration is ambiguous and its results are undefined. Whilst  
I feel that was demonstrated to be untrue, a request was made for this  
issue to be clarified.

So, for the rule:

   list-style: <type> <position> none;

MUST a user agent be able to apply:

   list-style-type: <type>;
   list-style-position: <position>;
   list-style-image: none;

for any combination of valid values?

Many thanks,
Mike


[1]  
<URL:http://groups.google.com/groups?threadm=qORgd.103011%24Ye1.5596%40amsnews05.chello.com>

     Subject: Opera and List-style-type?
      Author: "Samuël van Laere" <ometoon@chello.nl>
        Date: Sat, 30 Oct 2004 19:18:46 GMT
  Message-Id: qORgd.103011$Ye1.5596@amsnews05.chello.com

[2]  
<URL:http://groups.google.com/groups?threadm=opsgo9l1xpx13kvk%40atlantis>

     Subject: [bug] list-style shorthand property
      Author: "Michael Winter" <M.Winter@blueyonder.co.invalid>
        Date: Sat, 30 Oct 2004 20:23:51 GMT
  Message-Id: opsgo9l1xpx13kvk@atlantis

Received on Sunday, 31 October 2004 11:13:49 UTC