OpenErp 6.1 add submenu in installed module

Question

I have a module called MA, with a menu id = MMA in the other side I want to create module MB and add to MMA a sub menu id SmMMB, something like:

installed module's menu:

<menuitem name="MA" web_icon="images/ma.png" web_icon_hover="images/ma-hover.png" 
id="MMA" /> 
menuitem name="Configuration" id="menu_ma_c" parent="menu_ma" sequence="90"/>

new module's menu (which I want to add to already installed module and want it to be a submenu):

<menuitem name="MMB" id="MMA.SmMMB" parent ="MA.MMA" sequence="1"/>

I have no errors, neither sub menu

Answer 1

Make sure your submenu contains the action attribute like,

    <menuitem name="MMB" id="MMA.SmMMB" parent ="MA.MMA" 
                        sequence="1" action="mb_model_action"/>