diff --git a/test/processors/hybi00.cpp b/test/processors/hybi00.cpp
index ed012799d9..b95ba87d5c 100644
--- a/test/processors/hybi00.cpp
+++ b/test/processors/hybi00.cpp
@@ -59,6 +59,8 @@ struct processor_setup {
 	websocketpp::processor::hybi00<stub_config> p;
 };
 
+typedef stub_config::message_type::ptr message_ptr;
+
 BOOST_AUTO_TEST_CASE( exact_match ) {
 	processor_setup env(true);
     
@@ -167,3 +169,45 @@ BOOST_AUTO_TEST_CASE( extract_subprotocols ) {
     BOOST_CHECK( !env.p.extract_subprotocols(env.req,subps) );
     BOOST_CHECK_EQUAL( subps.size(), 0 );
 }
+
+BOOST_AUTO_TEST_CASE( prepare_data_frame_null ) {
+    processor_setup env(true);
+    
+    message_ptr in = env.msg_manager->get_message();
+    message_ptr out = env.msg_manager->get_message();
+    message_ptr invalid;
+
+
+    // empty pointers arguements should return sane error 
+    BOOST_CHECK_EQUAL( env.p.prepare_data_frame(invalid,invalid), websocketpp::processor::error::invalid_arguments );
+
+    BOOST_CHECK_EQUAL( env.p.prepare_data_frame(in,invalid), websocketpp::processor::error::invalid_arguments );
+
+    BOOST_CHECK_EQUAL( env.p.prepare_data_frame(invalid,out), websocketpp::processor::error::invalid_arguments );
+    
+    // test valid opcodes
+    // text (1) should be the only valid opcode
+    for (int i = 0; i < 0xF; i++) {
+        in->set_opcode(websocketpp::frame::opcode::value(i));
+        
+        env.ec = env.p.prepare_data_frame(in,out);
+        
+        if (i != 1) {
+            BOOST_CHECK_EQUAL( env.ec, websocketpp::processor::error::invalid_opcode );
+        } else {
+            BOOST_CHECK_NE( env.ec, websocketpp::processor::error::invalid_opcode );
+        }
+    }
+    
+    /*
+     * TODO: tests for invalid UTF8
+    char buf[2] = {0x00, 0x00};
+
+    in->set_opcode(websocketpp::frame::opcode::text);
+    in->set_payload("foo");
+
+    env.ec = env.p.prepare_data_frame(in,out);
+    BOOST_CHECK_EQUAL( env.ec, websocketpp::processor::error::invalid_payload );
+    */
+}
+
diff --git a/websocketpp/processors/hybi00.hpp b/websocketpp/processors/hybi00.hpp
index ca9e3a35dd..319e42d1df 100644
--- a/websocketpp/processors/hybi00.hpp
+++ b/websocketpp/processors/hybi00.hpp
@@ -39,6 +39,7 @@
 
 #include <websocketpp/processors/processor.hpp>
 
+#include <websocketpp/frame.hpp>
 #include <websocketpp/md5/md5.hpp>
 
 namespace websocketpp {
@@ -218,19 +219,39 @@ public:
 	 */
 	virtual lib::error_code prepare_data_frame(message_ptr in, message_ptr out)
 	{
-		// assert msg
+		if (!in || !out) {
+			return make_error_code(error::invalid_arguments);
+		}
 		
-		// check if the message is prepared already
+		// TODO: check if the message is prepared already
 		
 		// validate opcode
+        if (in->get_opcode() != frame::opcode::text) {
+            return make_error_code(error::invalid_opcode);    
+        }
+        
+        std::string& i = in->get_raw_payload();
+		//std::string& o = out->get_raw_payload();
+
 		// validate payload utf8
-		
-		// if we are a client generate a masking key
-		
+		if (!utf8_validator::validate(i)) {
+            return make_error_code(error::invalid_payload);
+        }
+
 		// generate header
-		// perform compression
-		// perform masking
+        char h = 0x00;
+        char f = 0xff;
+        out->set_header(std::string(&h,1));
+        
+        // process payload
+        out->set_payload(i);
+        out->append_payload(std::string(&f,1));
+
+		// hybi00 doesn't support compression
+		// hybi00 doesn't have masking
 		
+        out->set_prepared(true);
+
 		return lib::error_code();
 	}