diff --git a/hplip-preferences-crash.patch b/hplip-preferences-crash.patch
new file mode 100644
index 0000000..2436a5d
--- /dev/null
+++ b/hplip-preferences-crash.patch
@@ -0,0 +1,14 @@
+diff -up hplip-3.9.12/ui4/devmgr5.py.preferences-crash hplip-3.9.12/ui4/devmgr5.py
+--- hplip-3.9.12/ui4/devmgr5.py.preferences-crash	2009-12-15 21:22:17.000000000 +0000
++++ hplip-3.9.12/ui4/devmgr5.py	2010-01-20 12:21:27.794561868 +0000
+@@ -2020,7 +2020,9 @@ class DevMgr5(QMainWindow,  Ui_MainWindo
+         if dlg.exec_() == QDialog.Accepted:
+             self.user_settings.load()
+ 
+-            self.cur_device.sendEvent(EVENT_USER_CONFIGURATION_CHANGED, self.cur_printer)
++            if self.cur_device is not None:
++                self.cur_device.sendEvent(EVENT_USER_CONFIGURATION_CHANGED,
++                                          self.cur_printer)
+ 
+ 
+     # ***********************************************************************************
diff --git a/hplip.spec b/hplip.spec
index 9f4c536..9ab523e 100644
--- a/hplip.spec
+++ b/hplip.spec
@@ -13,6 +13,7 @@ Conflicts: selinux-policy < 3.0.3-3
 
 Url: http://hplip.sourceforge.net/
 Source0: http://kent.dl.sourceforge.net/sourceforge/hplip/%{name}-%{version}.tar.gz
+Patch1: hplip-preferences-crash.patch
 Patch2: hplip-strstr-const.patch
 Patch3: hplip-ui-optional.patch
 Patch4: hplip-no-asm.patch
@@ -109,6 +110,9 @@ SANE driver for scanners in HP's multi-function devices (from HPOJ).
 rm -rf $RPM_BUILD_DIR/%{name}-%{version}
 %setup -q
 
+# Fixed crash when using Preferences dialog (bug #555979).
+%patch1 -p1 -b .preferences-crash
+
 # Fix compilation.
 %patch2 -p1 -b .strstr-const
 
@@ -338,6 +342,9 @@ fi
 /usr/bin/update-desktop-database &>/dev/null ||:
 
 %changelog
+* Wed Jan 20 2010 Tim Waugh <twaugh@redhat.com> - 3.9.12-4
+- Fixed crash when using Preferences dialog (bug #555979).
+
 * Tue Jan 12 2010 Tim Waugh <twaugh@redhat.com> - 3.9.12-3
 - Do ship pkit module even though the PolicyKit mechanism is not
   shipped (bug #554817).