diff --git a/tix.spec b/tix.spec
index a28d944..9650712 100644
--- a/tix.spec
+++ b/tix.spec
@@ -5,7 +5,7 @@ Summary: A set of extension widgets for Tk
 Name: tix
 Epoch: 1
 Version: %{tixmajor}.0
-Release: 8
+Release: 9
 License: BSD
 Group: Development/Languages
 URL: http://tix.sourceforge.net/
@@ -15,6 +15,7 @@ Patch1: tix-%{version}-soname.patch
 BuildRoot: %{_tmppath}/%{name}-%{version}-root
 Requires: tcl >= %{tcltkver}, tk >= %{tcltkver}
 Buildrequires: tcl-devel >= %{tcltkver}, tk-devel >= %{tcltkver}
+BuildRequires: libX11-devel
 
 %description
 Tix, the Tk Interface eXtension, is a powerful set of user interface
@@ -125,6 +126,9 @@ rm -rf $RPM_BUILD_ROOT
 %doc docs/*
 
 %changelog
+* Mon May 15 2006 David Cantrell <dcantrell@redhat.com> - 1:8.4.0-9
+- BuildRequires libX11-devel
+
 * Thu Apr 20 2006 David Cantrell <dcantrell@redhat.com> - 1:8.4.0-8
 - Rebuild against Tcl/Tk 8.4.13