I have been struggling with this for 2 days.
Since I added text labels on the list of thumbnails on that page : http://hixair.fr/galleries/indexcopy.php
The page seems to load fine until it gets at the middle and thumbnails are overlapping.
What is wierd is if you open the code inspector, or rotate the display on an iPhone/ipad, things get refreshed and are displayed perfectly.
I tested with Safari mostly, issue is also present in the Galaxy SII browser. Seems fine with Firefox.
Some help will be really appreciated!!
(page validates as XHTML 1.0 Strict)
Setting the width and height on the images or their containing div via CSS (not using the html height attribute) should fix this problem for you.