Legend with both Individual layers and layer groups

[Carlo Calvino]

Hello everybody,
I make use of Mapserver 4.6 and Maplab 2.2. Thanks to GmapFactory, i was
able to create a webgis application. But I am not satisfied with the
legend. Let's suppose to have ten layers, I want to organize them in 5
individual layers, and the other five inside a group. That is something
like this:

[ ] Layer 1
[ ] Layer 2
[x] Layer 3
[x] Layer 4
[x] Layer 5
[x] Group layer #1
    [ ] Layer 6
    [x] Layer 7
    [ ] Layer 8
    [x] Layer 9
    [ ] Layer 10

Checkboxes can be off [ ] or on [x]. Any ideas how to achieve this aim?