I think it should be http://www.horde.org/webmail/ I was just going to change it, but the eclass sets the homepage..
+*horde-webmail-1.2.4 (16 Sep 2009) + + 16 Sep 2009; Alex Legler <a3li@gentoo.org> -horde-webmail-1.0.8.ebuild, + -horde-webmail-1.1.3.ebuild, -horde-webmail-1.2.ebuild, + +horde-webmail-1.2.4.ebuild: + Non-maintainer commit: Version bump for security bug 285052. Removing + vulnerable versions. Adding USE condition on the patch in SRC_URI. Fixing + homepage, closes bug 257694. +