When I add renderOnUserRole tag to my ice:menuItem, and it is not rendered (actually border of it is rendered), all ice:menuItem nested within this ice:menuItem are rendered (selecting of border, causes showing of this nested ice:menuItem).
Probably in other components which allows nesting another components it is brokent too.

I've investigated it, and here are more detailed info:
When user don't have roles specified in renderOnUserRole this div is rendered to output:
<div id="someId" class="iceMnuBarSubMenu" style="display: none;" name="SUBMENU"/>

But if iceMnuBarSubMenu CSS class contains non 0px border width it is rendered like in attached menu.jpg.

Probably when in FF I select this border some onmouseover javascript is triggering rendering of submenu containded by this menu.
(I saw this javascript code using FireBug).

To fix this bug don't render any component when user don't have roles specified in renderOnUserRole.

Alsa when I set rendered property to false, and removed renderOnUserRole it behaves the same.

This behavior is not present in IE.