"semantic" breaks mouse-bindings?

Hello, all.

I haven't been using Xemacs all that long, so I apologise if this is a
seemingly easy question to answer. I've just installed "semantic" for use
with Xemacs (via debian's package of it) which goes fine, yet whenever I
try to open a file (albeit a .c, or .java) the mouse-bindings to the menus
stop working, and Xemacs becomes inoperable.

Apart from the beeps that are audible, I can see the message: "Symbol's
value as variable is void: semantic-tfe-overlay". I have tried googling
for this to no avail. At present, removing semantic puts things back to
normal, but is there a fix for this?

Kindly,

-- Thomas Adam

--
I know nothing, and understand even less.