Bug in cyrus-sasl with GSSAPI, encoded packet size too big (4156 > 4096)

I have an ongoing problem when using cyrus-sasl > 2.1.23-14 with GSSAPI 
when trying to send any email over 4096 size. I got around the problem 
by installing 2.1.23-13 from a SRC RPM in CentOS6.6, since it was not 
available in repos.
I also was able to solve the problem by using the 2.1.23-15 SRC RPM and 
commenting out patch 41, which is  "patch41 -p1 -b .ad_compat". I was 
able to keep patch42 uncommented, so I have already narrowed it down to 
this ad_compat patch.

I recently tried on CentOS7 and installed everything from repo, 
configured the same setup which is a cyrus murder using proxyd services 
in imap config, and still get the same error. If I set it up with the 
same authentication mechanisms as a standalone server, it works ok.

On CentOS7 I used cyrus-sasl-2.1.26-19.2
rpm -qa | grep cyrus
cyrus-imapd-2.4.17-8.el7_1.x86_64
cyrus-sasl-lib-2.1.26-19.2.el7.x86_64
cyrus-imapd-utils-2.4.17-8.el7_1.x86_64
cyrus-sasl-2.1.26-19.2.el7.x86_64
cyrus-sasl-plain-2.1.26-19.2.el7.x86_64
cyrus-sasl-gssapi-2.1.26-19.2.el7.x86_64

Please view my bug submitted to RedHat for more details on my setup and 
configuration. At this point they would like the cyrus-sasl devs to take 
a look and see if they can help in any way.

Thank You,
Matt