diff -dur gnokii.orig/common/gsm-statemachine.c gnokii/common/gsm-statemachine.c
--- gnokii.orig/common/gsm-statemachine.c	2013-04-07 16:31:27.929885641 +0200
+++ gnokii/common/gsm-statemachine.c	2013-04-08 04:29:48.405936104 +0200
@@ -27,6 +27,9 @@
 	state->waiting_for_number = 0;
 	state->received_number = 0;
 
+	state->keepalive.tv_sec = 0;
+	state->keepalive.tv_usec = 0;
+	
 	return GN_ERR_NONE;
 }
 
@@ -42,12 +45,29 @@
 		state->last_msg = message;
 		state->current_state = GN_SM_MessageSent;
 
-		/* FIXME - clear KeepAlive timer */
+		state->keepalive.tv_sec = 0;
+		state->keepalive.tv_usec = 0;
+
 		return state->link.send_message(messagesize, messagetype, message, state);
 	}
 	else return GN_ERR_NOTREADY;
 }
 
+void sm_keepalive(struct gn_statemachine *state)
+{
+	gettimeofday(&(state->keepalive), NULL);
+}
+
+int sm_is_alive(struct timeval *timeout, struct gn_statemachine *state)
+{
+	struct timeval t, now;
+
+	timeradd(&(state->keepalive), timeout, &t);
+	gettimeofday(&now, NULL);
+	
+	return timercmp(&t, &now, >);
+}  
+
 GNOKII_API gn_state gn_sm_loop(int timeout, struct gn_statemachine *state)
 {
 	struct timeval loop_timeout;
@@ -67,7 +87,8 @@
 		state->link.loop(&loop_timeout, state);
 	}
 
-	/* FIXME - add calling a KeepAlive function here */
+	sm_keepalive(state);
+
 	return state->current_state;
 }
 
@@ -80,6 +101,9 @@
 		state->received_number = 0;
 		if (state->link.reset)
 			state->link.reset(state);
+
+		state->keepalive.tv_sec = 0;
+		state->keepalive.tv_usec = 0;
 	}
 }
 
@@ -234,7 +258,8 @@
 		do {
 			s = gn_sm_loop(1, state);  /* Timeout=100ms */
 			gettimeofday(&now, NULL);
-		} while (timercmp(&next, &now, >) && (s == GN_SM_MessageSent));
+		} while ((timercmp(&next, &now, >) || sm_is_alive(&timeout, state))
+			&& (s == GN_SM_MessageSent));
 		if (s == GN_SM_WaitingForResponse || s == GN_SM_ResponseReceived) break;
 
 		if (state->config.sm_retry) {
@@ -257,7 +282,8 @@
 	do {
 		s = gn_sm_loop(1, state);  /* Timeout=100ms */
 		gettimeofday(&now, NULL);
-	} while (timercmp(&next, &now, >) && (s != GN_SM_ResponseReceived));
+	} while ((timercmp(&next, &now, >) || sm_is_alive(&timeout, state))
+		&& (s != GN_SM_ResponseReceived));
 
 	if (s == GN_SM_ResponseReceived)
 		return sm_error_get(waitfor, state);
diff -dur gnokii.orig/include/gnokii/statemachine.h gnokii/include/gnokii/statemachine.h
--- gnokii.orig/include/gnokii/statemachine.h	2013-04-07 16:31:27.957885764 +0200
+++ gnokii/include/gnokii/statemachine.h	2013-04-08 04:26:38.220993018 +0200
@@ -79,6 +79,9 @@
 	union {
 		gn_phonebook_entry pb_entry;
 	} u;
+	
+	/* Store time of the last call to sm_keepalive() */
+	struct timeval keepalive;
 };
 
 GNOKII_API gn_state gn_sm_loop(int timeout, struct gn_statemachine *state);