escape space, etc in $memcached_key
diff --git a/src/core/ngx_string.c b/src/core/ngx_string.c
index 6a927b0..a07dbeb 100644
--- a/src/core/ngx_string.c
+++ b/src/core/ngx_string.c
@@ -1059,7 +1059,27 @@
         0xffffffff  /* 1111 1111 1111 1111  1111 1111 1111 1111 */
     };
 
-    static uint32_t  *map[] = { uri, args, html, refresh };
+                    /* " ", %00-%1F */
+
+    static uint32_t   memcached[] = {
+        0xffffffff, /* 1111 1111 1111 1111  1111 1111 1111 1111 */
+
+                    /* ?>=< ;:98 7654 3210  /.-, +*)( '&%$ #"!  */
+        0x00000001, /* 0000 0000 0000 0000  0000 0000 0000 0001 */
+
+                    /* _^]\ [ZYX WVUT SRQP  ONML KJIH GFED CBA@ */
+        0x00000000, /* 0000 0000 0000 0000  0000 0000 0000 0000 */
+
+                    /*  ~}| {zyx wvut srqp  onml kjih gfed cba` */
+        0x00000000, /* 0000 0000 0000 0000  0000 0000 0000 0000 */
+
+        0x00000000, /* 0000 0000 0000 0000  0000 0000 0000 0000 */
+        0x00000000, /* 0000 0000 0000 0000  0000 0000 0000 0000 */
+        0x00000000, /* 0000 0000 0000 0000  0000 0000 0000 0000 */
+        0x00000000, /* 0000 0000 0000 0000  0000 0000 0000 0000 */
+    };
+
+    static uint32_t  *map[] = { uri, args, html, refresh, memcached };
 
 
     escape = map[type];