diff --git a/rhn-client-tools.spec b/rhn-client-tools.spec
index 73ad32d..6284bdf 100644
--- a/rhn-client-tools.spec
+++ b/rhn-client-tools.spec
@@ -13,7 +13,7 @@
 Summary: Support programs and libraries for Red Hat Satellite or Spacewalk
 Name: rhn-client-tools
 Version: 2.8.16
-Release: 5%{?dist}
+Release: 6%{?dist}
 License: GPLv2
 Source0: https://github.com/spacewalkproject/spacewalk/archive/%{name}-%{version}.tar.gz
 URL:     https://github.com/spacewalkproject/spacewalk
@@ -290,6 +290,7 @@ Python 3 specific files for rhn-setup-gnome.
 make -f Makefile.rhn-client-tools
 
 %install
+export RHEL_ALLOW_PYTHON2_FOR_BUILD=1
 %if 0%{?build_py2}
 make -f Makefile.rhn-client-tools install VERSION=%{version}-%{release} \
         PYTHONPATH=%{python_sitelib} PYTHONVERSION=%{python_version} \
@@ -680,6 +681,10 @@ make -f Makefile.rhn-client-tools test
 %endif
 
 %changelog
+* Tue Jul 24 2018 Tomas Kasparek <tkasparek@redhat.com> 2.8.16-6
+- set RHEL_ALLOW_PYTHON2_FOR_BUILD=1 to enable using gtk-builder-convert during
+  build (tkasparek@redhat.com)
+
 * Mon Apr 16 2018 Tomas Kasparek <tkasparek@redhat.com> 2.8.16-5
 - Resolves: #1566025 - require latest provider of /usr/bin/gpg
   (tkasparek@redhat.com)