Virtual packages don't install any files, so there's nothing where a license could apply to. Therefore LICENSE should be the empty string for them. (This must not be confused with the license for the ebuild itself, which is GPL-2 and is in the ebuild's header.)
The issue becomes more important together with ACCEPT_LICENSE, since the user shouldn't be required to accept anything for installation of a virtual. If there are no objections, I'll remove all licenses from the virtual category (or rather ask fauli to do it with his keywording script). Similar for HOMEPAGE which should be the empty string too. Ulrich
