A question about the license of gnutls

Hi, 

I has a question about the license of gnutls, I don't know whether it is a bug.

In gnutls-3.6.13/LICENSE, the content is as following:
------------------------------------------------------------------
LICENSING
=========

Since GnuTLS version 3.1.10, the core library is released under
the GNU Lesser General Public License (LGPL) version 2.1 or later
(see doc/COPYING.LESSER for the license terms).

The GNU LGPL applies to the main GnuTLS library, while the
included applications as well as gnutls-openssl
library are under the GNU GPL version 3.  The gnutls library is
located in the lib/ and libdane/ directories, while the applications
in src/ and, the gnutls-openssl library is at extra/.
......
------------------------------------------------------------------

I think it means that all the license in lib/ is under the license of LGPL-2.1+. 
But the license of lib/x509/krb5.h and lib/x509/krb5.c is GPL-3.0+. Obviously, it is conflict with the content of LICENSE file. 
So, I don't know is it a bug or do I understand.

Best regards
Lei Maohui