Key to select all same nodes(same @id) except current

Hi Group,
            I am developing a key that will select all
occurrences (same @id) of current element except
current node.
The structure of my xml is

<category_list>
<category id="16277" sort_order="10">
    <category_list>
       <category id="16222" sort_order="10">
          ......occurrences of category_list and
category elements
       </category>
    </category_list>
</category>
<category id="16278" sort_order="10">
.......
</category>
</category_list>

My key: <xsl:key name="ParentKey" match="category"
use="@id"/>

Also I want to check whether any <category> elements
with same @id, exists in all top elements of current
<category> element.

Your help would be appreciated.

regards,
Ranjan


 
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