Apparently, the only change between Gaim 2.0_beta5 and Gaim 2.0_beta5-r1 is the ebuild file used. It seems to me there's been a mistake in making this new ebuild file; the "spell" USE flag is no longer listed in Gaim's IUSE, despite still appearing in the RDEPEND and G2CONF (under src_compile) as before.
Re-added spell iuse