diff --git a/scripts/configure b/scripts/configure
index 4cb2d8d7..3b604040 100755
--- a/scripts/configure
+++ b/scripts/configure
@@ -8072,7 +8072,7 @@ fi
       # Not available on all versions:  check for include file.
       SHLIB_CFLAGS="-fpic"
       LDDL_FLAGS="-shared ${LIB_SPECS}"
-      CFLAGS="${CFLAGS} -l/usr/X11R6/include"
+      CFLAGS="${CFLAGS} -L/usr/X11R6/include"
       ;;
 
     *-netbsd*|*-openbsd*)
diff --git a/scripts/configure.in b/scripts/configure.in
index b2070922..3000438e 100644
--- a/scripts/configure.in
+++ b/scripts/configure.in
@@ -1615,7 +1615,7 @@ if test $usingTcl ; then
       # Not available on all versions:  check for include file.
       SHLIB_CFLAGS="-fpic"
       LDDL_FLAGS="-shared ${LIB_SPECS}"
-      CFLAGS="${CFLAGS} -l/usr/X11R6/include"
+      CFLAGS="${CFLAGS} -L/usr/X11R6/include"
       ;;
       
     *-netbsd*|*-openbsd*)