diff --git a/doc/exit_codes.txt b/doc/exit_codes.txt
new file mode 100644
index 0000000..9071454
--- /dev/null
+++ b/doc/exit_codes.txt
@@ -0,0 +1,11 @@
+The exit codes of rdesktop are:
+
+0	 Everything went well. Specifically, the server sent a
+         RDP_PDU_DEACTIVATE which seems to be a signal that the
+         session has ended normally.
+
+1	 Usage error, i.e. wrong commandline option, invalid hostname
+	 or similar.
+
+2	 End of connection by other reason than received
+	 RDP_PDU_DEACTIVATE. 
\ No newline at end of file
diff --git a/proto.h b/proto.h
index 95c47b8..0364a10 100644
--- a/proto.h
+++ b/proto.h
@@ -75,7 +75,7 @@ void process_colour_pointer_pdu(STREAM s);
 void process_cached_pointer_pdu(STREAM s);
 void process_bitmap_updates(STREAM s);
 void process_palette(STREAM s);
-void rdp_main_loop(void);
+BOOL rdp_main_loop(void);
 BOOL rdp_connect(char *server, uint32 flags, char *domain, char *password, char *command,
 		 char *directory);
 void rdp_disconnect(void);
diff --git a/rdesktop.c b/rdesktop.c
index 4170764..6bfcd33 100644
--- a/rdesktop.c
+++ b/rdesktop.c
@@ -149,7 +149,7 @@ main(int argc, char *argv[])
 	char password[16];
 	char shell[128];
 	char directory[32];
-	BOOL prompt_password;
+	BOOL prompt_password, rdp_retval = False;
 	struct passwd *pw;
 	uint32 flags;
 	char *p;
@@ -366,6 +366,7 @@ main(int argc, char *argv[])
 
 #ifdef RDP2VNC
 	rdp2vnc_connect(server, flags, domain, password, shell, directory);
+	return 0;
 #else
 
 	if (!ui_init())
@@ -384,7 +385,7 @@ main(int argc, char *argv[])
 
 	if (ui_create_window())
 	{
-		rdp_main_loop();
+		rdp_retval = rdp_main_loop();
 		ui_destroy_window();
 	}
 
@@ -392,9 +393,13 @@ main(int argc, char *argv[])
 	rdp_disconnect();
 	ui_deinit();
 
+	if (True == rdp_retval) 
+		return 0;
+	else
+		return 2;
+
 #endif
 
-	return 0;
 }
 
 #ifdef EGD_SOCKET
diff --git a/rdp.c b/rdp.c
index e362097..314f781 100644
--- a/rdp.c
+++ b/rdp.c
@@ -849,7 +849,7 @@ process_data_pdu(STREAM s)
 }
 
 /* Process incoming packets */
-void
+BOOL
 rdp_main_loop(void)
 {
 	uint8 type;
@@ -864,6 +864,8 @@ rdp_main_loop(void)
 				break;
 
 			case RDP_PDU_DEACTIVATE:
+				DEBUG(("RDP_PDU_DEACTIVATE\n"));
+				return True;
 				break;
 
 			case RDP_PDU_DATA:
@@ -877,6 +879,7 @@ rdp_main_loop(void)
 				unimpl("PDU %d\n", type);
 		}
 	}
+	return False;
 }
 
 /* Establish a connection up to the RDP layer */