diff -u old/xorg-docs-1.4-r1.ebuild new/xorg-docs-1.4-r1.ebuild
--- old/xorg-docs-1.4-r1.ebuild	2007-09-09 15:52:53.000000000 -0400
+++ new/xorg-docs-1.4-r1.ebuild	2007-09-09 15:52:59.000000000 -0400
@@ -36,3 +36,12 @@
 
 # parallel build broken -- https://bugs.gentoo.org/show_bug.cgi?id=170798
 MAKEOPTS="${MAKEOPTS} -j1"
+
+pkg_setup() {
+	if ! built_with_use app-text/sgml-common jadetex ; then
+		eerror "sgml-common is missing jadetex support. Please add 'jadetex'"
+		eerror "to your USE flags, and re-emerge app-text/sgml-common."
+		die "app-text/sgml-common needs jadetex support"
+	fi
+}
+