hpijs-1.7.1 has been released; the ebuild for 1.6.1 merges fine if just renamed and the hpijs-1.4.1-rss.1.patch is re-used.
Have done what Dewet Diener suggested and emerged hpijs-1.7.1 . It works fine on my x86/gentoo-dev-sources 2.6.9-r1/udev system with an HP DeskJet 5740 which is supported since 1.7
*** Bug 73929 has been marked as a duplicate of this bug. ***
bumped to 1.7.1