The word "bookmark" does not exist in the type library, so the answer is probably No.
Possibly it could be done by remoting the UI (user interface) with AutoIt or something similar (programs that can send mouse clicks and key presses to other programs/windows on the screen). Might be difficult to know the correct place for the mouse click, though...
I see. Yeah, if you could toggle bookmarks on/off easily... that would be handy. In the meantime I'll stick with Find/Replace until one of you figures it out and is willing to share source code.