Grouping in a table

Hi, 
according to what i have learned from this list, i triesd to implement the 
following XSL:

<xsl:key name="categorise" match="value" use="C"/>

<fo:table-body>
                        <xsl:apply-templates select="elementlist[key='aktif']"/>
</fo:table-body>

<xsl:template match="elementlist">
        <xsl:apply-templates select="value[generate-id()= 
generate-id(key('categorise',C)[1])]" mode="catrows"/>
</xsl:template>

<xsl:template match="catrows">
        <fo:table-row>
                <xsl:apply-templates select="key('categorise',C)" mode="value"/>
        </fo:table-row>
</xsl:template>

<xsl:template match="value">
<fo:table-cell border-width="0.2mm" border-style="solid">
                  <fo:block text-align="left" font-size="8pt" >
                        <xsl:value-of select="A"/>
                  </fo:block>
                </fo:table-cell>
</xsl:template>

i try to create the following table:
A               B                   C                      D
--------------------------------------------------------------
110             asa                 110                   sss
--------------------------------------------------------------
2210            sas                 221                    sss
22110           sss                 221                    sa
22101           ssa                 221                    a
--------------------------------------------------------------
2220           ...


with an XML of:
<value>
<A>110</A>
<B>asa</B>
<C>110</C>
<D>sss</D>
</value>
.
.
.

(i guess i should use a table in table?)
thanks in advance.
regards