from; Bug#297981: libapache2-mod-encoding: FTBFS: 'regex_t' undeclared (first use in this function)
http://bugs.debian.org/297981

Thanks for Andreas Jochens.

--- ./mod_encoding.c	2004-06-15 17:52:25.000000000 +0200
+++ ./mod_encoding.c	2005-03-03 21:46:34.162465697 +0100
@@ -68,6 +68,7 @@
 
 */
 
+#include <regex.h>
 #include <httpd.h>
 #include <http_config.h>
 #include <http_core.h>