Explorer forces menu to pop up (not down)

[grace422]

Here is one of the pages on the site.

http://www.graspinc.com/methodology/reg-guide.htm

If you set your screen reolution to something big, like 1280 x 960, AND use Explorer, AND explorer adds a horizontal scroll bar, THEN the menu's drop-up, rather than down. You can also force the issue by simply making the browser window narrow to the point that the horizontal scroll bar appears.

Conversely, if you stretch the browser window so that the bottom scroll bar disappears, so does the error.

Any suggestions would be greatly appreciated.

[grace422]

I have found that if I make all the content of the site below the place where the menu appears, fixed width, then the error doesn't occur. See: http://www.graspinc.com/Untitled-2.htm

Anyone know how I can keep the rest of the page variable width and have the menu behave properly? I realize I should just re-do the site in pure non-tables CSS, but this is an old and huge site, and they aren't up for that.

Any suggestions would be greatly appreciated.