Images not resized in Introduction Package (except if quality or effect is defined)

I just installed Introduction packages (got same result using 4.4.7 and 4.5.3) and I cannot get the images inserted into my page to be resized AUTOMATICALLY to the maxW or maxWinText value (template -> tt_content).

BUT... curiously if in the content bloc I defined either a Quality or an effect, the resize is done! Of course if I define there the width of the image, resize is also done.

Is that a known problem or am I missing something in my config?

I must say I cannot understand why defining an effect, suddenly the image is resized.

Hope someone can help me on this issue.
Regards,
Ben

It's definitely a bug with jb_gd_resize extension. Solution is described in the following article:
http://www.pixelplant.ro/en/articles/article-detail/article/helping-tt-news-and-jb-gd-resize-properly-resize-article-pictures.html