diff --git a/include/proto/buffers.h b/include/proto/buffers.h
index a5ad208..ca88b16 100644
--- a/include/proto/buffers.h
+++ b/include/proto/buffers.h
@@ -22,6 +22,8 @@
 #ifndef _PROTO_BUFFERS_H
 #define _PROTO_BUFFERS_H
 
+#include <stdlib.h>
+
 #include <common/config.h>
 #include <types/buffers.h>
 
@@ -84,6 +86,21 @@
 int buffer_replace(struct buffer *b, char *pos, char *end, char *str);
 int buffer_replace2(struct buffer *b, char *pos, char *end, char *str, int len);
 
+/*
+ * frees the destination chunk if already allocated, allocates a new string,
+ * and copies the source into it. The pointer to the destination string is
+ * returned, or NULL if the allocation fails or if any pointer is NULL..
+ */
+static inline char *chunk_dup(struct chunk *dst, const struct chunk *src) {
+	if (!dst || !src || !src->str)
+		return NULL;
+	if (dst->str)
+		free(dst->str);
+	dst->len = src->len;
+	dst->str = (char *)malloc(dst->len);
+	memcpy(dst->str, src->str, dst->len);
+	return dst->str;
+}
 
 #endif /* _PROTO_BUFFERS_H */
 
diff --git a/include/proto/httperr.h b/include/proto/httperr.h
new file mode 100644
index 0000000..24a0cd1
--- /dev/null
+++ b/include/proto/httperr.h
@@ -0,0 +1,41 @@
+/*
+  include/proto/httperr.h
+  This file contains declarations for HTTP responses and errors.
+
+  Copyright (C) 2000-2006 Willy Tarreau - w@1wt.eu
+  
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation, version 2.1
+  exclusively.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#ifndef _PROTO_HTTPERR_H
+#define _PROTO_HTTPERR_H
+
+#include <types/httperr.h>
+
+extern const int http_err_codes[HTTP_ERR_SIZE];
+extern const char *http_err_msgs[HTTP_ERR_SIZE];
+extern const char *HTTP_200;
+extern const char *HTTP_302;
+extern const char *HTTP_303;
+extern const char *HTTP_401_fmt;
+
+#endif /* _PROTO_HTTPERR_H */
+
+/*
+ * Local variables:
+ *  c-indent-level: 8
+ *  c-basic-offset: 8
+ * End:
+ */
diff --git a/include/proto/proto_http.h b/include/proto/proto_http.h
index 61d58c2..5ee3a53 100644
--- a/include/proto/proto_http.h
+++ b/include/proto/proto_http.h
@@ -40,10 +40,10 @@
 int process_cli(struct session *t);
 int process_srv(struct session *t);
 
-void client_retnclose(struct session *s, int len, const char *msg);
-void client_return(struct session *s, int len, const char *msg);
+void client_retnclose(struct session *s, const struct chunk *msg);
+void client_return(struct session *s, const struct chunk *msg);
 void srv_close_with_err(struct session *t, int err, int finst,
-			int status, int msglen, const char *msg);
+			int status, const struct chunk *msg);
 
 int produce_content(struct session *s);
 void debug_hdr(const char *dir, struct session *t, const char *start, const char *end);
diff --git a/include/types/httperr.h b/include/types/httperr.h
index c594048..c466328 100644
--- a/include/types/httperr.h
+++ b/include/types/httperr.h
@@ -32,6 +32,19 @@
 #define DATA_ST_INIT	0
 #define DATA_ST_DATA	1
 
+/*
+ * All implemented return codes
+ */
+enum {
+	HTTP_ERR_400 = 0,
+	HTTP_ERR_403,
+	HTTP_ERR_408,
+	HTTP_ERR_500,
+	HTTP_ERR_502,
+	HTTP_ERR_503,
+	HTTP_ERR_504,
+	HTTP_ERR_SIZE
+};
 
 
 #endif /* _TYPES_HTTPERR_H */
diff --git a/include/types/proxy.h b/include/types/proxy.h
index a82f195..8480143 100644
--- a/include/types/proxy.h
+++ b/include/types/proxy.h
@@ -34,6 +34,7 @@
 #include <common/regex.h>
 
 #include <types/buffers.h>
+#include <types/httperr.h>
 #include <types/session.h>
 #include <types/server.h>
 
@@ -125,22 +126,7 @@
 	int grace;				/* grace time after stop request */
 	char *check_req;			/* HTTP or SSL request to use for PR_O_HTTP_CHK|PR_O_SSL3_CHK */
 	int check_len;				/* Length of the HTTP or SSL3 request */
-	struct {
-		char *msg400;			/* message for error 400 */
-		int len400;			/* message length for error 400 */
-		char *msg403;			/* message for error 403 */
-		int len403;			/* message length for error 403 */
-		char *msg408;			/* message for error 408 */
-		int len408;			/* message length for error 408 */
-		char *msg500;			/* message for error 500 */
-		int len500;			/* message length for error 500 */
-		char *msg502;			/* message for error 502 */
-		int len502;			/* message length for error 502 */
-		char *msg503;			/* message for error 503 */
-		int len503;			/* message length for error 503 */
-		char *msg504;			/* message for error 504 */
-		int len504;			/* message length for error 504 */
-	} errmsg;
+	struct chunk errmsg[HTTP_ERR_SIZE];	/* default or customized error messages for known errors */
 };
 
 extern struct proxy *proxy;