As http://bugs.gentoo.org/show_bug.cgi?id=26161 I'm afraid the custom icon sets need updating again. Missing: search_xpm, mini_bug_xpm, mini_ok_xpm. They can be downloaded from http://www.dillo.org/Icons/ now. Also, there are now two new icon sets, pixmaps.trad.h and pixmaps.cobalt.h.
Thanks for reporting. I added trad and cobalt icon sets and updated the rest.