diff --git a/yum-3.4.3-comps.patch b/yum-3.4.3-comps.patch
new file mode 100644
index 0000000..dec503b
--- /dev/null
+++ b/yum-3.4.3-comps.patch
@@ -0,0 +1,15 @@
+diff -up yum-3.4.3/yum/comps.py.old yum-3.4.3/yum/comps.py
+--- yum-3.4.3/yum/comps.py.old	2013-05-02 11:02:28.000000000 -0400
++++ yum-3.4.3/yum/comps.py	2013-05-02 11:03:20.438942937 -0400
+@@ -373,7 +373,10 @@ class Environment(CompsObj):
+                 optionid = child.text
+                 self._options[optionid] = 1
+                 defopt = child.attrib.get('default')
+-                default = parse_boolean(defopt)
++                if defopt:
++                    default = parse_boolean(defopt)
++                else:
++                    default = False
+                 if default:
+                     self._defaultoptions[optionid] = 1
+ 
diff --git a/yum.spec b/yum.spec
index dce8e0a..7c838bb 100644
--- a/yum.spec
+++ b/yum.spec
@@ -41,7 +41,7 @@ BuildRequires: bash-completion
 Summary: RPM package installer/updater/manager
 Name: yum
 Version: 3.4.3
-Release: 88%{?dist}
+Release: 89%{?dist}
 License: GPLv2+
 Group: System Environment/Base
 Source0: http://yum.baseurl.org/download/3.4/%{name}-%{version}.tar.gz
@@ -52,6 +52,7 @@ Patch4: no-more-exactarchlist.patch
 Patch5: geode-arch.patch
 Patch6: yum-HEAD.patch
 Patch7: yum-ppc64-preferred.patch
+Patch10: yum-3.4.3-comps.patch
 Patch20: yum-manpage-files.patch
 Patch21: yum-completion-helper.patch
 
@@ -176,6 +177,7 @@ Install this package if you want auto yum updates nightly via cron.
 %patch5 -p1
 %patch6 -p1
 %patch7 -p1
+%patch10 -p1
 %patch20 -p1
 %patch21 -p1
 %patch1 -p1
@@ -402,6 +404,9 @@ exit 0
 %endif
 
 %changelog
+* Thu May  2 2013 Bill Nottingham <notting@redhat.com> - 3.4.3-89
+- Fix defaults-for-environment optional groups change. BZ 958531
+
 * Tue Apr 30 2013 James Antill <james at fedoraproject.org> - 3.4.3-88
 - update to latest HEAD.
 - Allow default on Environment optional groups.