Effect .show - not working well in IE

Effect .show - not working well in IE

Hi,

I'm using a hover function to .show/.hide a layer with the attribute "normal".
This works well in FF, the layer fades in smoothly. Trying the same with
IE there is a problem. The layer appears at once without any fadeIn effect.
But clicking on the close button the layer fades out correctly. Any idea
what could cause this behaviour?

thanks

T.C.