Ie8 problem : zooming browser scrollbar is not shown

Dear friends

my html file have frameset nested.
each frameset have image or html file.
when zooming more than 100% browser. then some menu item in html is invisible. It is only in ie8 happened.
but in ie7 get scroolbar it is ok.
meta tag is used for compability view purpose. there are no effect.

pls find me idea on above issue.

with regrads and thanks