[TYPO3] Download problem i jm_gallery

[Claus Bach]

I have used jm_gallery before. Then the download facility worked like a 
"normal" file download - i got the question - do you want to save or 
open the file ?

But know in my new 4.0.1 site, the image just shoews up in the browser - 
no dialog. I would like if I was asked if I want to download, but if it 
just opened in a new browser window, it would be fine.

Can anybody help ?

Claus Bach