Index: configure.ac
===================================================================
--- libcaca/configure.ac
+++ libcaca-new/configure.ac
@@ -225,7 +225,7 @@ if test "${enable_x11}" != "no"; then
   AC_CHECK_LIB(X11, XOpenDisplay,
    [ac_cv_my_have_x11="yes"
     if test -n "${x_includes}"; then X_CFLAGS="-I${x_includes}"; fi
-    if test -n "${x_libraries}"; then X_LIBS="-L${x_libraries}"; fi
+    if test -n "${x_libraries}" -a "${x_libraries}" != "/usr"; then X_LIBS="-L${x_libraries}"; fi
     AC_DEFINE(USE_X11, 1, Define to 1 to activate the X11 backend driver)
     CPPFLAGS="${CPPFLAGS} ${X_CFLAGS}"
     X11_LIBS="${X11_LIBS} -lX11 ${X_LIBS}"