diff --git a/extensions/rt_busypeers/rtbusy_conf.l b/extensions/rt_busypeers/rtbusy_conf.l
new file mode 100644
index 0000000..fe819bf
--- /dev/null
+++ b/extensions/rt_busypeers/rtbusy_conf.l
@@ -0,0 +1,107 @@
+/*********************************************************************************************************
+* Software License Agreement (BSD License)                                                               *
+* Author: Sebastien Decugis <sdecugis@freediameter.net>							 *
+*													 *
+* Copyright (c) 2013, WIDE Project and NICT								 *
+* All rights reserved.											 *
+* 													 *
+* Redistribution and use of this software in source and binary forms, with or without modification, are  *
+* permitted provided that the following conditions are met:						 *
+* 													 *
+* * Redistributions of source code must retain the above 						 *
+*   copyright notice, this list of conditions and the 							 *
+*   following disclaimer.										 *
+*    													 *
+* * Redistributions in binary form must reproduce the above 						 *
+*   copyright notice, this list of conditions and the 							 *
+*   following disclaimer in the documentation and/or other						 *
+*   materials provided with the distribution.								 *
+* 													 *
+* * Neither the name of the WIDE Project or NICT nor the 						 *
+*   names of its contributors may be used to endorse or 						 *
+*   promote products derived from this software without 						 *
+*   specific prior written permission of WIDE Project and 						 *
+*   NICT.												 *
+* 													 *
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED *
+* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A *
+* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR *
+* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 	 *
+* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 	 *
+* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR *
+* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF   *
+* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.								 *
+*********************************************************************************************************/
+
+/* Tokenizer
+ *
+ */
+
+%{
+#include "rtbusy.h"
+#include "rtbusy_conf.tab.h"
+
+/* Update the column information */
+#define YY_USER_ACTION { 						\
+	yylloc->first_column = yylloc->last_column + 1; 		\
+	yylloc->last_column = yylloc->first_column + yyleng - 1;	\
+}
+
+/* Avoid warning with newer flex */
+#define YY_NO_INPUT
+
+%}
+
+qstring		\"[^\"\n]*\"
+
+
+%option bison-bridge bison-locations
+%option noyywrap
+%option nounput
+
+%%
+
+	/* Update the line count */
+\n			{
+				yylloc->first_line++; 
+				yylloc->last_line++; 
+				yylloc->last_column=0; 
+			}
+	 
+	/* Eat all spaces but not new lines */
+([[:space:]]{-}[\n])+	;
+	/* Eat all comments */
+#.*$			;
+
+	/* Recognize any integer */
+[-]?[[:digit:]]+	{
+				/* Convert this to an integer value */
+				int ret=0;
+				ret = sscanf(yytext, "%i", &yylval->integer);
+				if (ret != 1) {
+					/* No matching: an error occurred */
+					TRACE_ERROR("Unable to convert the value '%s' to a valid number: %s", yytext, strerror(errno));
+					return LEX_ERROR; /* trig an error in yacc parser */
+					/* Maybe we could REJECT instead of failing here? */
+				}
+				return INTEGER;
+			}
+			
+	
+	
+	/* The key words */	
+(?i:"SkipTooBusyErrors")	 	{	return SKIPTOOBUSYERRORS;	}
+(?i:"RetryDistantPeers")	 	{	return RETRYDISTANTPEERS;	}
+(?i:"RetryMaxPeers")	 		{	return RETRYMAXPEERS;		}
+(?i:"RelayTimeout")	 		{	return RELAYTIMEOUT;		}
+			
+	/* Valid single characters for yyparse */
+[=;]			{ return yytext[0]; }
+
+	/* Unrecognized sequence, if it did not match any previous pattern */
+[^[:space:]=;\n]+	{ 
+				TRACE_ERROR("Unrecognized text on line %d col %d: '%s'.", yylloc->first_line, yylloc->first_column, yytext);
+			 	return LEX_ERROR; 
+			}
+
+%%