Please remove the dependencies virtual/{pdfviewer,psviewer,textbrowser} from all app-office/lyx app-text/docbook-sgml-utils ebuilds or drop a line, if you want me to do it. Reasoning: http://groups.google.de/group/linux.gentoo.dev/browse_thread/thread/894b903a4df38844/3c52933176a59ce1?lnk=st&q=questionable+usefulness+of+virtual%2Fpdfviewer%2Cpsviewer&rnum=1#3c52933176a59ce1
Done.