iTunes Album Artwork/Growl question

So I've installed "Growl" a notification system for my mac. Whenever I play a song in itunes or if i have my itunes on shuffle it displays the album artwork along with the song and artist in the top right hand corner of my screen.

BUT, I notice that even if I have the artwork in iTunes it'll display the album artwork as if I don't have it, like it'll show the generic "you don't have artwork for this album" icon. Is there something I have to do in order for other apps to be able to see my album artwork in itunes?

anyone?

It'll display the album artwork if the artwork is also attached to each song - whenever it does it, quickly check itunes tracks in the rest of the album to see which don't have the artwork on them - quick copy paste and should be fine.

Otherwise, I have no idea.