Possible to use wildcards in schema element names?

Hi all,
I'm trying to generate a schema for some xml (for which I have no
control over the format)
Consider the following xml example:
<?xml version="1.0" encoding="UTF-8"?>
<document>
   <name>Bill</name>
   <field1>abc</field1> <!-- any number of fields -->
   <field2>def</field2>
   <field3>ghi</field3>
   <field4>jkl</field4>

   <name>John</name>
   <field3>uvw</field3> <!-- need not start with field1 -->
   <field4>xyz</field4>
</document>

As you can see, each "name" element has a varying number of "field*" siblings.
So, I've come with the following attempt (the eagle-eyed among you,
may notice that I'm no expert):
<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
elementFormDefault="qualified">
 <xs:element name="document">
   <xs:complexType>
     <xs:sequence>
       <xs:choice maxOccurs="unbounded">
         <xs:element ref="name"/>
         <xs:element ref="field" maxOccurs="unbounded"/>
       </xs:choice>
     </xs:sequence>
   </xs:complexType>
 </xs:element>
 <xs:element name="name" type="xs:NCName"/>
 <xs:element name="field*" type="xs:NCName"/> <!-- How is it possible
to perform wildcard? -->
</xs:schema>

My question then is, "Is it possible, in the schema, to use wildcards
or regex for the field elements?

Many thanks in anticipation - Jimmy