[scribus] Images with a transparent background?

[Jim Ford]

If I export a document as a PDF and it has an image with a transparent
background, the background prints as black - which is not what I want
(or probably not what anybody wants!). This happens with Scribus
1.3.3.14, but not with 1.3.8, which prints OK.

Is this a bug in 1.3.3.14, or (as is more probable!) me not having
1.3.3.14 set-up properly?

Jim