I had the same problem, and found that it was because the rewrite engine was rewriting the icons (and stylesheets). I updated the rewrite rule in the virtualhost to ignore /packages/styles (for stylesheets), and /share (for icons).
# eZpublish config
DocumentRoot /www/ezpublish/current
RewriteEngine On
RewriteRule !(^/design|^/var/.*/storage|^/var/storage|^/extension/.*/design|^/kernel/setup/packages|^/packages/styles|^/share).*\.(gif|jpg|png|css|jar|js|ico|pdf)$ /www/ezpublish/current/index.php
There may be other directories that should be added to this list, but I just installed the beta last night so thats I'll I noticed. :-)