"Heading" items in the actions pane

In the actions pane, I can add actions, action groups and separators 
(horizontal lines).

We have quite a few actions and I was wondering if it's possible to add 
plain text item into the ActionsPaneItemCollection to serve as a
"heading" 
for separating various categories of actions?

I notice the IIS snap-in does this in its own actions pane, e.g., when you 
select a web site in the scope pane there are action "headings" (in
bold) 
such as "Manage Application" and "Edit Application".
However, it seems the 
IIS console renders its own Actions pane (if I just run mmc.exe, load the IIS 
snap-in and enable the Actions pane, there are 2 actions panes!).

I've tried adding an action and disabling it, but then it's greyed out and 
doesn't look much like a heading.

Any ideas appreciated.

Thanks,