diff --git a/owlps-listener/Makefile b/owlps-listener/Makefile
index 97cda13..c8c6f56 100644
--- a/owlps-listener/Makefile
+++ b/owlps-listener/Makefile
@@ -34,12 +34,13 @@ DEPFLAGS = -MMD
 XCFLAGS = $(CFLAGS) $(DEPFLAGS) $(WARN) $(HEADERS)
 PICFLAG = -fPIC
 OWLPSFLAGS = -D OWLPS_VERSION=\"$(OWLPS_VERSION)\"
-OWLPSFLAGS += -D USE_PTHREAD -pthread
 OWLPSFLAGS += -D USE_CONFIG_FILE -lconfuse
+OWLPSFLAGS += -D USE_PTHREAD -pthread
+#OWLPSFLAGS += -D ENABLE_KEEP_MONITOR -liw
 #OWLPSFLAGS += -D NDEBUG
 LIBS = -L$(LIBOWLPS_DIR) -lowlps \
 	-L$(LIBOWLPSCLIENT_DIR) -lowlps-client \
-	-lpcap -liw
+	-lpcap
 
 OS := $(shell uname)
 ifeq ("$(OS)", "Linux")
@@ -89,6 +90,7 @@ purge : clean
 help :
 	@echo "Needed libraries:"
 	@echo "	libpcap0.8-dev"
+	@echo "	libiw-dev (optionnal)"
 	@echo "	libconfuse-dev (optionnal)"
 	@echo "	libowlps-dev"
 	@echo
diff --git a/owlps-listener/Makefile_atheros_openwrt-10.03 b/owlps-listener/Makefile_atheros_openwrt-10.03
index 88f00ec..9184f6c 100644
--- a/owlps-listener/Makefile_atheros_openwrt-10.03
+++ b/owlps-listener/Makefile_atheros_openwrt-10.03
@@ -39,7 +39,7 @@ PICFLAG = -fPIC
 LOWLPS = -L$(LIBOWLPS_DIR) -lowlps
 LOWLPSA = $(LIBOWLPS_DIR)/libowlps.a
 LOWLPSCLIENTA = $(LIBOWLPSCLIENT_DIR)/libowlps-client.a
-LIBS = -lpcap -liw -lm -lrt $(LOWLPSCLIENTA)
+LIBS = -lpcap -lm -lrt $(LOWLPSCLIENTA)
 DYNAMIC_LIBS = $(TOOLCHAIN1)/lib/ld-uClibc.so.0
 SEMISTATIC_LIBS = $(DYNAMIC_LIBS)
 STATIC_LIBS =
@@ -48,8 +48,9 @@ LATHEROS = -L$(TOOLCHAIN1)/lib -L$(TOOLCHAIN1)/usr/lib \
 	#-L$(TOOLCHAIN2)/root-atheros/lib
 IATHEROS = -I$(TOOLCHAIN1)/usr/include -I$(TOOLCHAIN2)/usr/include
 OWLPSFLAGS = -D OWLPS_VERSION=\"$(OWLPS_VERSION)\"
-OWLPSFLAGS += -D USE_PTHREAD -pthread
 OWLPSFLAGS += -D USE_CONFIG_FILE -lconfuse
+OWLPSFLAGS += -D USE_PTHREAD -pthread
+#OWLPSFLAGS += -D ENABLE_KEEP_MONITOR -liw
 #OWLPSFLAGS += -D NDEBUG
 LDFLAGS = $(OWLPSFLAGS) $(LIBS)
 
diff --git a/owlps-listener/Makefile_atheros_openwrt-8.09 b/owlps-listener/Makefile_atheros_openwrt-8.09
index c5e4586..b3067cf 100644
--- a/owlps-listener/Makefile_atheros_openwrt-8.09
+++ b/owlps-listener/Makefile_atheros_openwrt-8.09
@@ -39,13 +39,14 @@ PICFLAG = -fPIC
 LOWLPS = -L$(LIBOWLPS_DIR) -lowlps
 LOWLPSA = $(LIBOWLPS_DIR)/libowlps.a
 LOWLPSCLIENTA = $(LIBOWLPSCLIENT_DIR)/libowlps-client.a
-LIBS = -lpcap -liw -lrt $(LOWLPSCLIENTA)
+LIBS = -lpcap -lrt $(LOWLPSCLIENTA)
 STATIC_LIBS = -lm
 LATHEROS = -L$(TOOLCHAIN_USR)/lib -L$(TOOLCHAIN_USR_2)/lib
 IATHEROS = -I$(TOOLCHAIN_USR)/include -I$(TOOLCHAIN_USR_2)/include
 OWLPSFLAGS = -D OWLPS_VERSION=\"$(OWLPS_VERSION)\"
-OWLPSFLAGS += -D USE_PTHREAD -pthread
 #OWLPSFLAGS += -D USE_CONFIG_FILE -lconfuse
+OWLPSFLAGS += -D USE_PTHREAD -pthread
+#OWLPSFLAGS += -D ENABLE_KEEP_MONITOR -liw
 #OWLPSFLAGS += -D NDEBUG
 LDFLAGS = $(OWLPSFLAGS) $(LIBS)
 
diff --git a/owlps-listener/owlps-listener.h b/owlps-listener/owlps-listener.h
index d04a5ec..4554ee1 100644
--- a/owlps-listener/owlps-listener.h
+++ b/owlps-listener/owlps-listener.h
@@ -10,9 +10,15 @@
  */
 //#define USE_CONFIG_FILE // Use libconfuse to read a config file
 //#define USE_PTHREAD // POSIX threads available?
+//#define ENABLE_KEEP_MONITOR // Enable the -K option (requires USE_PTHREAD)
 
 #define DEBUG
 
+#ifdef ENABLE_KEEP_MONITOR
+# ifndef USE_PTHREAD
+#  error "The option ENABLE_KEEP_MONITOR requires the option USE_PTHREAD"
+# endif // USE_PTHREAD
+#endif // ENABLE_KEEP_MONITOR
 
 #include <owlps.h>
 #include <owlps-client.h>
@@ -168,10 +174,10 @@ int check_configuration(void) ;
 void print_configuration(void) ;
 #endif // DEBUG
 
-#ifdef USE_PTHREAD
+#ifdef ENABLE_KEEP_MONITOR
 void* keep_mode_monitor(void *iface) ;
 int iface_mode_monitor(const char *const iface) ;
-#endif // USE_PTHREAD
+#endif // ENABLE_KEEP_MONITOR
 int capture(void) ;
 void read_packet(u_char *args, const struct pcap_pkthdr *header,
                  const u_char *packet) ;
@@ -211,12 +217,12 @@ void print_version(void) ;
   (cfg_setstr(cfg, "aggregation_ip", (IP)))
 #define GET_AGGREGATION_IP() \
   (cfg_getstr(cfg, "aggregation_ip"))
-#ifdef USE_PTHREAD
+#ifdef ENABLE_KEEP_MONITOR
 #define SET_KEEP_MONITOR() \
   (cfg_setbool(cfg, "keep_monitor", cfg_true))
 #define GET_KEEP_MONITOR() \
   (cfg_getbool(cfg, "keep_monitor"))
-#endif // USE_PTHREAD
+#endif // ENABLE_KEEP_MONITOR
 #define SET_AGGREGATION_PORT(PORT) \
   (cfg_setint(cfg, "aggregation_port", (PORT)))
 #define GET_AGGREGATION_PORT() \
@@ -298,12 +304,12 @@ void print_version(void) ;
   (strncpy(options.aggregation_ip, (IP), INET_ADDRSTRLEN))
 #define GET_AGGREGATION_IP() \
   (options.aggregation_ip)
-#ifdef USE_PTHREAD
+#ifdef ENABLE_KEEP_MONITOR
 #define SET_KEEP_MONITOR() \
   (options.keep_monitor = owl_true)
 #define GET_KEEP_MONITOR() \
   (options.keep_monitor)
-#endif // USE_PTHREAD
+#endif // ENABLE_KEEP_MONITOR
 #define SET_AGGREGATION_PORT(PORT) \
   (options.aggregation_port = (PORT))
 #define GET_AGGREGATION_PORT() \
diff --git a/owlps-listener/owlps-listenerd.c b/owlps-listener/owlps-listenerd.c
index af6456d..5e9e271 100644
--- a/owlps-listener/owlps-listenerd.c
+++ b/owlps-listener/owlps-listenerd.c
@@ -23,9 +23,12 @@
 
 #ifdef USE_PTHREAD
 # include <pthread.h>
-# include <iwlib.h>
 #endif // USE_PTHREAD
 
+#ifdef ENABLE_KEEP_MONITOR
+# include <iwlib.h>
+#endif // ENABLE_KEEP_MONITOR
+
 // Used by get_mac_addr():
 #include <netinet/udp.h>
 #include <netinet/ip.h>
@@ -61,9 +64,9 @@ struct {
   char aggregation_ip[INET_ADDRSTRLEN] ;
   uint_fast16_t aggregation_port ;
   uint_fast16_t listening_port ;
-#ifdef USE_PTHREAD
+#ifdef ENABLE_KEEP_MONITOR
   owl_bool keep_monitor ;
-#endif // USE_PTHREAD
+#endif // ENABLE_KEEP_MONITOR
   char rtap_iface[IFNAMSIZ + 1] ;
   char wifi_iface[IFNAMSIZ + 1] ;
 #ifdef USE_PTHREAD
@@ -85,9 +88,9 @@ struct {
   "127.0.0.1",
   OWL_DEFAULT_LISTENER_PORT,
   OWL_DEFAULT_REQUEST_PORT,
-#ifdef USE_PTHREAD
+#ifdef ENABLE_KEEP_MONITOR
   owl_false,
-#endif // USE_PTHREAD
+#endif // ENABLE_KEEP_MONITOR
   "",
   "",
 #ifdef USE_PTHREAD
@@ -112,10 +115,12 @@ int main(int argc, char *argv[])
   int ret ; // Program return value
 #ifdef USE_PTHREAD
   pthread_t
-    keep_monitor_thread,
     autocalibration_thread,
     autocalibration_hello_thread ;
 #endif // USE_PTHREAD
+#ifdef ENABLE_KEEP_MONITOR
+  pthread_t keep_monitor_thread ;
+#endif // ENABLE_KEEP_MONITOR
 
   owl_run = owl_true ;
 
@@ -142,6 +147,7 @@ int main(int argc, char *argv[])
 
 #ifdef USE_PTHREAD
   /* Set up threads */
+# ifdef ENABLE_KEEP_MONITOR
   if (GET_KEEP_MONITOR())
     {
       ret = pthread_create(&keep_monitor_thread, NULL,
@@ -153,6 +159,7 @@ int main(int argc, char *argv[])
           goto exit ;
         }
     }
+# endif // ENABLE_KEEP_MONITOR
 
   if (GET_AUTOCALIBRATION())
     {
@@ -181,6 +188,7 @@ int main(int argc, char *argv[])
   /* Wait for the threads to terminate */
 
 #ifdef USE_PTHREAD
+# ifdef ENABLE_KEEP_MONITOR
   if (GET_KEEP_MONITOR())
     {
       if (VERBOSE_WARNING)
@@ -190,6 +198,7 @@ int main(int argc, char *argv[])
       else if (VERBOSE_WARNING)
         fprintf(stderr, "OK.\n") ;
     }
+# endif // ENABLE_KEEP_MONITOR
 
   if (GET_AUTOCALIBRATION())
     {
@@ -290,11 +299,11 @@ int parse_config_file(int argc, char **argv)
       CFG_INT("aggregation_port", OWL_DEFAULT_LISTENER_PORT, CFGF_NONE),
       // Port on which mobiles send active requests:
       CFG_INT("listening_port", OWL_DEFAULT_REQUEST_PORT, CFGF_NONE),
-#ifdef USE_PTHREAD
+#ifdef ENABLE_KEEP_MONITOR
       // Activate the active monitor mode keeping-up (read the code if
       // you do not understand what I mean):
       CFG_BOOL("keep_monitor", cfg_false, CFGF_NONE),
-#endif // USE_PTHREAD
+#endif // ENABLE_KEEP_MONITOR
       // Radiotap interface, used to capture:
       CFG_STR("rtap_iface", "", CFGF_NONE),
       // Physical interface corresponding to the radiotap interface (used
@@ -463,14 +472,13 @@ int parse_main_options(int argc, char **argv)
 #endif // USE_PTHREAD
           break ;
         case 'K' :
-#ifdef USE_PTHREAD
+#ifdef ENABLE_KEEP_MONITOR
           SET_KEEP_MONITOR() ;
-#else // USE_PTHREAD
+#else // ENABLE_KEEP_MONITOR
           fprintf(stderr, "Warning! The program was compiled without"
-                  " support of POSIX threads, so -K (monitor mode"
-                  " keeping-up) is not available and will be ignored."
-                  "\n") ;
-#endif // USE_PTHREAD
+                  " enabling the -K option (monitor mode keeping-up)."
+                  ".\n") ;
+#endif // ENABLE_KEEP_MONITOR
           break ;
         case 'l' :
           SET_LISTENING_PORT(strtol(optarg, NULL, 0)) ;
@@ -658,8 +666,10 @@ void print_configuration()
           "listening_port = %"PRIuFAST16"\n"
           "rtap_iface = \"%s\"\n"
           "wifi_iface = \"%s\"\n"
-#ifdef USE_PTHREAD
+#ifdef ENABLE_KEEP_MONITOR
           "keep_monitor = %s\n"
+#endif // ENABLE_KEEP_MONITOR
+#ifdef USE_PTHREAD
           "autocalibration = %s\n"
           "autocalibration_ip = \"%s\"\n"
           "autocalibration_request_port = %"PRIuFAST16"\n"
@@ -680,8 +690,10 @@ void print_configuration()
           GET_LISTENING_PORT(),
           GET_RTAP_IFACE(),
           GET_WIFI_IFACE(),
-#ifdef USE_PTHREAD
+#ifdef ENABLE_KEEP_MONITOR
           OWL_BOOL_TO_STRING(GET_KEEP_MONITOR()),
+#endif // ENABLE_KEEP_MONITOR
+#ifdef USE_PTHREAD
           OWL_BOOL_TO_STRING(GET_AUTOCALIBRATION()),
           GET_AUTOCALIBRATION_IP(),
           GET_AUTOCALIBRATION_REQUEST_PORT(),
@@ -694,14 +706,14 @@ void print_configuration()
           GET_MY_POSITION_Y(),
           GET_MY_POSITION_Z(),
 #endif // USE_PTHREAD
-          OWL_BOOL_TO_STRING(GET_VERBOSE()),
+          OWL_BOOL_TO_STRING(GET_VERBOSE())
           ) ;
 #endif // USE_CONFIG_FILE
 }
 
 
 
-#ifdef USE_PTHREAD
+#ifdef ENABLE_KEEP_MONITOR
 /*
  * Thread function. Switches interface 'iface' to monitor mode every
  * second.
@@ -754,7 +766,7 @@ int iface_mode_monitor(const char *const iface)
 
   return 0 ;
 }
-#endif // USE_PTHREAD
+#endif // ENABLE_KEEP_MONITOR
 
 
 
@@ -1498,8 +1510,8 @@ void print_usage()
          "Other options:\n"
          "\t-K\tKeep the monitor mode up on wifi_iface. Use it with buggy"
          " drivers that disable monitor mode periodically. Available"
-         " only if the program was compiled with support of POSIX"
-         " threads.\n"
+         " only if the program was compiled with the option"
+         " ENABLE_KEEP_MONITOR.\n"
          "\t-v\tBe verbose. You can use this option up to 3 times to"
          " increase the level of verbosity (1 = warnings, 2 = useful"
          " information, 3 = a lot of information, 4 = display each"
@@ -1527,24 +1539,31 @@ void print_version()
          " System project.\n"
          "Version: %s.\n"
          "Compilation-time options:\n"
+         "\tSupport for configuration file (libconfuse): %s.\n"
          "\tSupport for POSIX threads: %s.\n"
-         "\tSupport for configuration file (libconfuse): %s.\n",
+         "\tOption -K: %s.\n",
 #ifdef OWLPS_VERSION
          OWLPS_VERSION
 #else // OWLPS_VERSION
          "unknown version"
 #endif // OWLPS_VERSION
          ,
+#ifdef USE_CONFIG_FILE
+         "YES"
+#else // USE_CONFIG_FILE
+         "NO"
+#endif // USE_CONFIG_FILE
+         ,
 #ifdef USE_PTHREAD
          "YES"
 #else // USE_PTHREAD
          "NO"
 #endif // USE_PTHREAD
          ,
-#ifdef USE_CONFIG_FILE
+#ifdef ENABLE_KEEP_MONITOR
          "YES"
-#else // USE_CONFIG_FILE
+#else // ENABLE_KEEP_MONITOR
          "NO"
-#endif // USE_CONFIG_FILE
+#endif // ENABLE_KEEP_MONITOR
          ) ;
 }