portage upgrade today :)

[ebuild     U ] app-shells/bash-3.1_p5-r2 [3.1_p5] USE="-afs -bashlogger -build -nls -unicode" 0 kB
[ebuild     U ] x11-terms/xterm-208 [207] USE="truetype -Xaw3d -doc -toolbar -unicode" 732 kB
[ebuild     U ] sys-apps/baselayout-1.12.0_pre14-r2 [1.12.0_pre13-r1] USE="-bootstrap -build -static -unicode" 208 kB
[ebuild     U ] sys-fs/udev-081 [079] 189 kB
[ebuild  NS   ] sys-kernel/gentoo-sources-2.6.15-r1  USE="-build -doc -symlink" 187 kB
[ebuild     U ] dev-java/blackdown-jdk-1.4.2.03-r2 [1.4.2.03] USE="X% alsa% -browserplugin -doc -mozilla -nsplugin" 0 kB
[ebuild     U ] app-misc/pax-utils-0.1.7-r1 [0.1.6] USE="-caps" 47 kB
[ebuild     U ] sys-apps/man-pages-2.21 [2.20] USE="-nls" 1,704 kB
[ebuild     U ] dev-libs/libxml2-2.6.23 [2.6.22] USE="python readline -debug -doc -ipv6" 3,338 kB
[ebuild     U ] x11-libs/gtk+-2.8.10 [2.8.9] USE="jpeg tiff -debug -doc -xinerama%" 11,683 kB
[ebuild     U ] perl-core/MIME-Base64-3.07 [3.05] 15 kB
[ebuild     U ] perl-core/digest-base-1.14 [1.13] 7 kB
[ebuild     U ] perl-core/Digest-MD5-2.36 [2.33] 43 kB
[ebuild     U ] dev-perl/HTML-Parser-3.48 [3.46] USE="-unicode" 80 kB
[ebuild     U ] dev-java/rhino-1.5.5-r2 [1.5.5-r1] USE="-doc -jikes -source%" 0 kB
[ebuild     U ] dev-perl/CDDB_get-2.27 [2.25] 21 kB
[ebuild     U ] mail-client/sylpheed-2.2.0_beta4 [2.2.0_beta2] USE="crypt ssl -gnome -ipv6 -ldap -nls -pda -xface" 2,398 kB
[ebuild     U ] x11-themes/gtk-engines-2.6.7 [2.6.6] USE="-accessibility -debug" 468 kB
[ebuild     U ] app-cdr/cdrecord-prodvd-2.01.01_p03 [2.01.01-r1] 338 kB

dev-java/rhino がエラーでこける。なぜ?