While building app-text/kchmviewer-4.0_beta2 I get the error: ui_tab_bookmarks.h:13:42: error: Qt3Support/Q3MimeSourceFactory: No such file or directory which causes the build to stop. I believe the error is caused because Qt 4 was not built with the qt3support USE flag. If this is the case, the fix would obviously be to check for this USE flag in qt before compiling.
Thank you for report, Dror. I hope fixed now. Hope because I'm sure this fix does not work with splitted qt-4.4_rc1. But after reading of qt4.eclass it seems that solution should work with qt-4.4 (final release) and as qt-4.4_rc1 is removed from the tree I've commited fix. Please, if you have some time and good internet connection test that it's possible to install kchmviewer with qt-4.4 and reopen this bug. FIXED.