yeah but it works when you have multiple words. In my case, there is only one which is 1234567890...DEF (md5 -> 32 chars) And I would need the possibility to do m=1234567890...DEF m[1] = 1 m[2] = 2 .. m[32] = F A mere rewrite is impossible here.. It seems indeed, Larry Posted at Nginx Forum: http://forum.nginx.org/read.php?2,238015,238029#msg-238029