Line 623 of emerge, print " ", self.getInstallationStatus(catpack) except... there isn't any catpackage var yet. Could easily do print " ", self.getInstallationStatus(mycat+'/'+mypkg) instead. Note, unless the user is running w/ quiet, this appears to break emerge -S everytime.
Fixed in CVS.
Fixed in portage-2.0.50-r1