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diff --git a/doc/examples/xor_ciph.cpp b/doc/examples/xor_ciph.cpp
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+/*
+  An implementation of the highly secure (not) XOR cipher. AKA, how to write
+  and use your own cipher object. DO NOT make up your own ciphers. Please.
+
+  Written by Jack Lloyd ([email protected]) on Feb 17, 2004
+
+  This file is in the public domain
+*/
+#include <botan/base.h>
+#include <botan/init.h>
+using namespace Botan;
+
+class XOR_Cipher : public StreamCipher
+   {
+   public:
+      // what we want to call this cipher
+      std::string name() const { return "XOR"; }
+      // return a new object of this type
+      StreamCipher* clone() const { return new XOR_Cipher; }
+      // StreamCipher() can take a number of args, which are:
+      //   min keylen, max keylen, keylength mod, iv size
+      //   In this case we just pass min keylen, which means the
+      //   only keysize we support is 1 byte, and don't use an IV.
+      XOR_Cipher() : StreamCipher(1) { mask = 0; }
+   private:
+      void cipher(const byte[], byte[], u32bit);
+      void key(const byte[], u32bit);
+      byte mask;
+   };
+
+void XOR_Cipher::cipher(const byte in[], byte out[], u32bit length)
+   {
+   for(u32bit j = 0; j != length; j++)
+      out[j] = in[j] ^ mask;
+   }
+
+void XOR_Cipher::key(const byte key[], u32bit)
+   {
+   /* We know length == 1 because it is checked in set_key against the
+      constraints we passed to StreamCipher's constructor. In this case,
+      we said: "All keys are of length 1 byte and no other length".
+
+      An excercise for the reader would be to extend this to support
+      arbitrary length (for arbitrary in the range 1-32) keys.
+   */
+   mask = key[0];
+   }
+
+#include <fstream>
+#include <iostream>
+#include <string>
+#include <vector>
+#include <cstring>
+
+#include <botan/look_add.h>
+#include <botan/lookup.h>
+#include <botan/filters.h>
+
+int main()
+   {
+   LibraryInitializer init;
+
+   add_algorithm(new XOR_Cipher); // make it available to use
+   add_alias("Vernam", "XOR");  // make Vernam an alias for XOR
+
+   SymmetricKey key("42"); // a key of length 1, value hex 42 == dec 66
+
+   /*
+    Since stream ciphers are typically additive, the encryption and
+    decryption ops are the same, so this isn't terribly interesting.
+
+    If this where a block cipher you would have to add a cipher mode and
+    padding method, such as "/CBC/PKCS7".
+   */
+   Pipe enc(get_cipher("XOR", key, ENCRYPTION), new Hex_Encoder);
+   Pipe dec(new Hex_Decoder, get_cipher("Vernam", key, DECRYPTION));
+
+   // I think the pigeons are actually asleep at midnight...
+   std::string secret = "The pigeon flys at midnight.";
+
+   std::cout << "The secret message is '" << secret << "'" << std::endl;
+
+   enc.process_msg(secret);
+   std::string cipher = enc.read_all_as_string();
+
+   std::cout << "The encrypted secret message is " << cipher << std::endl;
+
+   dec.process_msg(cipher);
+   secret = dec.read_all_as_string();
+
+   std::cout << "The decrypted secret message is '"
+             << secret << "'" << std::endl;
+
+   return 0;
+   }