Richfaces: rich:datatable rowspan using rich:subtable

I use Richfaces, Seam and JSF, and I want something like the following:

and I have managed it to a degree using a rich:subtable like this:

<rich:dataTable
value="#{backingBean.companyList}"
rows="100"
var="company">
<f:facet name="header">
    <rich:columnGroup>
        <rich:column>Company Name</rich:column>
        <rich:column>Company Email</rich:column>
        <rich:column>Product Name</rich:column>
        <rich:column>Product Ema开发者_如何学Goil</rich:column>
    </rich:columnGroup>
</f:facet>
<rich:subTable value="#{company.products}" var="product" rowKeyVar="rowKey">
    <rich:column rowspan="#{company.products.size()}" rendered="#{rowKey eq 0}">
        #{company.name}
    </rich:column>
    <rich:column rowspan="#{company.products.size()}" rendered="#{rowKey eq 0}">
        #{company.email}
    </rich:column>
    <rich:column>
        #{product.name}
    </rich:column>
    <rich:column>
        #{product.email}
    </rich:column>
</rich:subTable>

the problem is that companies that have NO products, do not get rendered at all. What I want would be for them to be rendered, and the remaining row (the product-specific columns) to be empty.

Is there a way to do this?

Note: I have also tried nested rich:datatables, but the internal columns do not overlap with the outer columns containing the header. With rich:subtable the inner columns overlap with the outer columns and show nice.

UPDATE:

I created a Google Code project (a simple Maven project) that shows exactly what the problem is.

http://code.google.com/p/richfaces-rowspan/

Follow-up discussion with answer (actually a Richfaces issue) in Richfaces forum.

http://community.jboss.org/message/541819#541819