Tablehead breaks rowspan with colspan

[Demosteneus]

Hi,

As a variation of bug 279:

If we have a cell that has both rowspan and colspan and we want to print this inside a tablehead, the publishing fails.

data.xml

<table>
    <th>
        <td colspan="2" rowspan="2">H1</td>
        <td colspan="1" rowspan="1">H2</td>
        <td colspan="1" rowspan="1">H3</td>
    </th>
    <th>
        <td colspan="1" rowspan="1">H2</td>
        <td colspan="1" rowspan="1">H3</td>
    </th>
    <tr>
        <td colspan="1" rowspan="1">1</td>
        <td colspan="1" rowspan="1">2</td>
        <td colspan="1" rowspan="1">3</td>
        <td colspan="1" rowspan="1">4</td>
    </tr>
    <tr>
        <td rowspan="2" colspan="1">1</td>
        <td colspan="1" rowspan="1">2</td>
        <td colspan="1" rowspan="1">3</td>
        <td colspan="1" rowspan="1">4</td>
    </tr>
    <tr>
        <td colspan="1" rowspan="1">2</td>
        <td colspan="1" rowspan="1">3</td>
        <td colspan="1" rowspan="1">4</td>
    </tr>
</table>

layout.xml

<Layout xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="layoutschema-en.xsd" xmlns:sd="urn:speedata:2009/publisher/functions/en" xmlns="urn:speedata.de:2009/publisher/en" xmlns:xi="http://www.w3.org/2001/XInclude" version="4.2.0">
    <Record element="table">
        <PlaceObject>
            <Table width="170mm">
                <Columns>
                    <Column width="42.5mm" align="center" />
                    <Column width="42.5mm" align="center" />
                    <Column width="42.5mm" align="center" />
                    <Column width="42.5mm" align="center" />
                </Columns>
                <Tablehead>
                <ForAll select="th">
                    <Tr>
                        <ForAll select="td">
                            <Td rowspan="{@rowspan}" colspan="{@colspan}" border-left="1pt" border-right="1pt" border-top="1pt" border-bottom="1pt">
                                <Paragraph>
                                    <Value select="string(.)"/>
                                </Paragraph>
                            </Td>
                        </ForAll>
                    </Tr>
                </ForAll>
                </Tablehead>
                <ForAll select="tr">
                    <Tr>
                        <ForAll select="td">
                            <Td rowspan="{@rowspan}" colspan="{@colspan}" border-left="1pt" border-right="1pt" border-top="1pt" border-bottom="1pt">
                                <Paragraph>
                                    <Value select="string(.)"/>
                                </Paragraph>
                            </Td>
                        </ForAll>
                    </Tr>
                </ForAll>
            </Table>
        </PlaceObject>
    </Record>
</Layout>

If we delete the tablehead, the publishing works as expected.