flickering dhtml image map in msie

[roseplant]

hi,
i'm hoping someone can help me with this one, it's really driving me nuts. from the page (http://tr.freewebsitehost.net/) it's clear what I'm trying to do. a clickable image map with transparent gif overlays. when you hold the mouse over a province of Turkey it turks yellow (done by transparent gif overlays and SPANs). but the map seems to flicker each time the mouse is moved to a different area... however there is no problem in firefox! i'd really appreciate if someone can help me sort this one out - I'm sure its just some simple tag I've overlooked, but i just can't find it!

roseplant