--- libx11-1.3.3.orig/configure.ac
+++ libx11-1.3.3/configure.ac
@@ -547,7 +547,7 @@
 	   x11.pc
 	   x11-xcb.pc])
 
-man_pages_suffix=$LIBMAN_SUFFIX
+man_pages_suffix=$LIB_MAN_SUFFIX
 if test -z "$man_pages_suffix"; then
     man_pages_suffix=none
 fi