Empty choice in a group ?

Hi,

Is the following  allowed :

<xs:group name="empty.Grp">
  <xs:choice/>
 </xs:group>

I do not have any validation problem with xsv, sqc, xsdvalid, ect...  and do not see any information
in the specification...
But msxml detect an error :
empty.xsd#/schema[1]/group[position() = 1 and @name = 'empty.Grp']/choice[1] Empty can be satisfied only if {minOccurs = 0}. 

What is the correct answer ? 

Thanks in advance

-- bruno -- 
Bruno Chatel
Tel : (+33) (0)4 96 11 14 57
bcha@chadocs.com
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