[Plugin: Dropdown Menu Widget] Menu is not visble behind some images

Hi,

I have issues with part of the drop down menu being obscured by an image in IE – FF is OK though. The menu seems to be behind the image. Is there a way I can rectify this?

https://www.rusticstone.net/_DEV/house-signs/freestanding/

If you view the link with IE you should see what I mean.

Thanks loads in advance. I hope you can help.

Jez,