datatable dont renders a detail correct if a UIColumns is used

The detailStamp facet dont use the full size of table because of the colspan-attribute of the detail-table is not not rendered for all dynamic uicolumns.
Lets say we have a datatable with 3 UIColumn-Elements and 1 UIColumns-Element with 3 more dynamic UIColumns, now the renderer will render a colspan of 4 and not as expected 6.

To solve this problem we changed the method renderDetailRow(..) (line 147) in HtmlDataTableRenderer as shown below:

//writer.writeAttribute(HTML.COLSPAN_ATTR,new Integer(uiData.getChildren().size()) ,null);
int count = 0;
List<UIComponent> list = uiData.getChildren();
for (UIComponent component : list) {
if (component instanceof UIColumns)

{ UIColumns v = (UIColumns) component; count += v.getRowCount(); }

else

{ count++; }

}
writer.writeAttribute(HTML.COLSPAN_ATTR,new Integer(count) ,null);