diff --git a/thunderbird-mozconfig b/thunderbird-mozconfig
index b756a7c..14999b7 100644
--- a/thunderbird-mozconfig
+++ b/thunderbird-mozconfig
@@ -1,7 +1,7 @@
 mk_add_options MOZ_CO_PROJECT=mail
 ac_add_options --enable-application=mail
 mk_add_options MOZ_OBJDIR=@TOPSRCDIR@/objdir-tb/
-mk_add_options AUTOCONF=autoconf-2.13
+#mk_add_options AUTOCONF=autoconf-2.13
 
 #ac_add_options --with-system-png
 
diff --git a/thunderbird.spec b/thunderbird.spec
index d1d6a27..9c4588f 100644
--- a/thunderbird.spec
+++ b/thunderbird.spec
@@ -2,6 +2,7 @@
 %define nspr_version 4.6
 %define nss_version 3.10
 %define cairo_version 1.0
+%define autoconf_version 2.13
 
 %define official_branding 1
 
@@ -48,6 +49,7 @@ Requires:       nss >= %{nss_version}
 %if 0%{?rhel} >= 5
 Requires:       launchmail
 %endif
+BuildRequires:  autoconf >= %{autoconf_version}
 BuildRequires:  cairo-devel >= %{cairo_version}
 BuildRequires:  libpng-devel, libjpeg-devel, gtk2-devel
 BuildRequires:  zlib-devel, gzip, zip, unzip