as described in the url with double click set, you can't drag and drop or move items. it works when single click is set. the patch http://quickgit.kde.org/index.php?p=kde-baseapps.git&a=blobdiff&h=937e6b21687d4c00c236543ddc31e465467d01ee&hp=83c28f75fbff7e3e384f9abc7f6acca3a2a36818&hb=e7abae8338fe932799ca9bf62c4664cdd47ce8cc&f=plasma/applets/folderview/iconview.cpp fixes it. please apply to portage.
Created attachment 262073 [details, diff] Aseigo's patch
Fixed in 4.6.2 (out real soon now :)