From: Hans Petter Jansson <hpj@copyleft.no>
      Wolfgang Rosenauer <wr@rosenauer.org>
Subject: use libnsssharedhelper if available at compile time
         (can be disabled by exporting MOZ_XRE_NO_NSSHELPER=1)
References:

diff --git a/config/autoconf.mk.in b/config/autoconf.mk.in
--- a/config/autoconf.mk.in
+++ b/config/autoconf.mk.in
@@ -458,16 +458,20 @@ MOZ_PANGO_LIBS          = @MOZ_PANGO_LIB
 XT_LIBS			= @XT_LIBS@
 
 MOZ_ALSA_LIBS           = @MOZ_ALSA_LIBS@
 
 GLIB_CFLAGS	= @GLIB_CFLAGS@
 GLIB_LIBS	= @GLIB_LIBS@
 GLIB_GMODULE_LIBS	= @GLIB_GMODULE_LIBS@
 
+MOZ_ENABLE_NSSHELPER = @MOZ_ENABLE_NSSHELPER@
+NSSHELPER_CFLAGS = @NSSHELPER_CFLAGS@
+NSSHELPER_LIBS = @NSSHELPER_LIBS@
+
 MOZ_NATIVE_MAKEDEPEND	= @SYSTEM_MAKEDEPEND@
 
 MOZ_AUTO_DEPS	= @MOZ_AUTO_DEPS@
 COMPILER_DEPEND = @COMPILER_DEPEND@
 MDDEPDIR        := @MDDEPDIR@
 CC_WRAPPER = @CC_WRAPPER@
 CXX_WRAPPER = @CXX_WRAPPER@
 
diff --git a/configure.in b/configure.in
--- a/configure.in
+++ b/configure.in
@@ -6759,16 +6759,31 @@ AC_SUBST(QCMS_LIBS)
 
 dnl ========================================================
 dnl HarfBuzz
 dnl ========================================================
 MOZ_HARFBUZZ_LIBS='$(DEPTH)/mozilla/gfx/harfbuzz/src/$(LIB_PREFIX)mozharfbuzz.$(LIB_SUFFIX)'
 AC_SUBST(MOZ_HARFBUZZ_LIBS)
 
 dnl ========================================================
+dnl Check for nss-shared-helper
+dnl ========================================================
+
+  PKG_CHECK_MODULES(NSSHELPER, nss-shared-helper, 
+   [MOZ_ENABLE_NSSHELPER=1],
+   [MOZ_ENABLE_NSSHELPER=])
+
+if test "$MOZ_ENABLE_NSSHELPER"; then
+  AC_DEFINE(MOZ_ENABLE_NSSHELPER)
+fi
+AC_SUBST(MOZ_ENABLE_NSSHELPER)
+AC_SUBST(NSSHELPER_CFLAGS)
+AC_SUBST(NSSHELPER_LIBS)
+
+dnl ========================================================
 dnl disable xul
 dnl ========================================================
 MOZ_ARG_DISABLE_BOOL(xul,
 [  --disable-xul           Disable XUL],
     MOZ_XUL= )
 if test "$MOZ_XUL"; then
   AC_DEFINE(MOZ_XUL)
 fi
diff --git a/mail/app/Makefile.in b/mail/app/Makefile.in
--- a/mail/app/Makefile.in
+++ b/mail/app/Makefile.in
@@ -107,16 +107,17 @@ endif
 
 APP_XPCOM_LIBS = $(XPCOM_GLUE_LDOPTS)
 
 LIBS += \
 	$(STATIC_COMPONENTS_LINKER_PATH) \
 	$(EXTRA_DSO_LIBS) \
 	$(APP_XPCOM_LIBS) \
 	$(NSPR_LIBS) \
+	$(NSSHELPER_LIBS) \
 	$(NULL)
 
 ifdef MOZ_JPROF
 LIBS += -ljprof
 endif
 
 ifdef MOZ_ENABLE_DBUS
 LIBS += $(MOZ_DBUS_GLIB_LIBS)