My problem was that as happen with many the ThickBox stoped working after being rendered on AJAX (in my particular case using Prototype Framework).
Solution: on the bottom of your xHTML answer, or making it simple, in the end of your partial render add this code:
tb_init('a.thickbox, area.thickbox, input.thickbox');
imgLoader = new Image();
imgLoader.src = tb_pathToImage;
But if you are using
jQuery.noConflict(); probably if you are playing with JQuery and Prototype on the same page, then replace ‘$’ with ‘jQuery’
The solution was found on this Forum: http://community.xajaxproject.org/viewtopic.php?id=5528, very smart guys
Tested on FF 3, IE 6,7
MAke some comment! Its open!