Javascript Menues Remain Visible Even Though Mouse Is Not Over Them

I've been given the task of mantaining and fixing a website which I
didn't design.

I'm using Internet Explorer 5.5 and 6.x. Specifically, the problem is that navigation menues (written in javascript) don't disappear when the mouse moves outside of the area of the menues (some of the menues are nested two and three levels). As long as the mouse cursor remains *within* the options of the menues, the option under the mouse cursor is highlighted and the corresponding
sub-menu is displayed. If the mouse pointer then moves over another
option of the menu then the former sub-menu hides, the new option is
highlighted and its corresponding sub-menu is displayed, or, in case of
a nested sub-menu, the corresponding sub-menu is displayed. So far so
good.

As I said before, the problem arises when the mouse pointer moves *out*
of the menu area. In this case, the last menu + sub-menu (if available)
+ sub-sub-menu (if available) remain visible treading any underlying
content, instead of auto-hiding after half a second, for example, as is
the case of all well designed websites.

As far as I could find out, the original programmer used some
third-party tool to design the menues, and the javascript code was
automatically generated by that tool. By the way, the code ....