Clicking on RibbonBar/ButtonItem

I have problem simulating button clicks on this control item:

The ClassName of the control is "DevComponents.DotNetBar.RibbonBar".

I can access the menu itself using 'Items' property:

[AppName].WinFormsObject('ribbonCtrl').WinFormsObject('rbManageServices').WinFormsObject('rbServices').Items.Item(0)

The ClassName of the menu item is "DevComponents.DotNetBar.ButtonItem".

The problem that I'm having is I couldn't click on the menu as there seems to be no 'Click' or 'Select' methods available against the menu item.

Has anyone done this before? Is there any other method that I could use instead?

Thanks.