With the conversion of linux-sources to a new-style virtual today, all old-style virtuals are gone from the portage tree. See GLEP 37 and bug 350792 for details.
Thanks to everyone who has helped with conversion or cleanup. I hope that I didn't step on too many toes for the conversions I did myself. I suggest that a warning for PROVIDE should be added to repoman, mainly to prevent unintentional readdition of old-style virtuals when ebuilds are copied from an overlay to the main tree. Ulrich