accessing the DTD

I would like to produce comboboxes or radio buttons based on the list of valid
values for an attribute.  My DTD has the valid values but I can't seem to get
access to the set.  I can get to the active value of the attribute only.

<!ELEMENT car (#PCDATA)>
<!ATTLIST car color (red|yellow|blue) "red">

<car color="blue"/>

This gives me the color of the car, blue, but not the fact that the color could
have been red or yellow.

<xsl:template match="car">
  color is <xsl:value-of select="@color"/>
</xsl:template>

I've checked the FAQ, the draft and various other links but can't find the
magic.  Thoughts anyone?
Thanks,
Larry Mason



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