[TYPO3] caching problem dam, tt_news, rgsmoothgallery

[Matyi Gábor]

Hi!

I use the dam, tt_news, rgsmoothgallery plugins for showing a picture gallery. 
I have lot's of images. After I add some new images to a tt_news entry. and I 
open the page where the tt_news lists appear, the page load very slow or I 
get the "premature and of script header: index.php error.

I examined that the problem occurs  because the thumbnail images of the new 
added images haven't generated in the folder typo3temp/pic yet. It seem to be 
a slow progress.
If I wait some hour, the thumbnail generation pass in the background. After 
this the pages with the new added images comes perfectly.

My question, why this thumbnail generation so slow? Why I get this premature 
and of sccipt header after 30 sec? In the php.ini the max_execution time is 
300. (5 min).

Thanks

Gabor