Image Upload problem related to dimensions

I seem to have a problem with the images I upload on my image gallery...

I created an image gallery using CCK, views, imagecache and image pager. My content type is just with a title, a first image uploader that I use as an icon, and a second image uploader with mutiple values. Everything works well, I can upload images and it resized according to imagecache, and displayed like a gallery using image pager inside each node, but it seems that when an image dimension is too big, it will not be displayed in the gallery...

So if I upload 10 pics, and some of them are really big. like over 1400px/1400px, I can see the preview of the pics right after I upload them (when creating the gallery), but after submitting, the image gallery only display the name of the images that are too big, and display normally the ones that are smaller.
After few tries, I realised that it's not related to the size of the file, some small jpeg with a very high compression but very large dimensions are not displayed when some other jpeg bigger size but smaller dimensions, are displayed...

Anyone as an answer to my problem ? ^_^