diff --git a/configure.ac b/configure.ac
index d58b8c2f1c27587e7faeabacc4d4470ea435356b..45b11ae4c74fb2bd87ad43f51434540473abac56 100644
--- a/configure.ac
+++ b/configure.ac
@@ -50,7 +50,7 @@ AC_PATH_XTRA
 
 # Checks for header files.
 AC_HEADER_STDC
-AC_CHECK_HEADERS([malloc.h unistd.h X11/Xlib.h X11/Xutil.h X11/extensions/Xext.h],,
+AC_CHECK_HEADERS([malloc.h unistd.h X11/Xlib.h X11/Xutil.h],,
 		 [AC_MSG_ERROR([Exiting...])])
 AC_CHECK_HEADERS([GL/gl.h GL/glx.h rpc/xdr.h],,[AC_MSG_ERROR([Exiting...])])