For example bug 465986 comment #6, in "can be found at 0" there should be an URI instead of the number 0. http://www.gentoo.org/ <- should be http COLON SLASH SLASH www DOT gentoo DOT org SLASH
The URL is returned correctly from the XML-RPC API (pybugz), so this seems to be a rendering problem on the web UI.
This is fixed in our instance, as well in upstream code (albeit differently).