It looks like the setting of WANT_AUTOCONF=2.57 in the ebuild does not prevent the package from being emerged (because the variable is set just before the invocation of autoconf, and not globally for the ebuild file). Nevertheless, this should be fixed. WANT_AUTOCONF=2.5 is probably what is meant.
Marking this bug as blocking bug 192923. This is a slightly different issue, since this package should emerge fine, but it is related, so I consider this OK. If you feel different, please change it back.
(In reply to comment #0) > this should be fixed. WANT_AUTOCONF=2.5 is probably what is meant. I solved it in a much easier way. There is a cleaner and more recent version already in Portage that has even better keywording, so I deleted that one. Denis.