Index: src/network/network_client.cpp
===================================================================
--- src/network/network_client.cpp	(revision 12594)
+++ src/network/network_client.cpp	(working copy)
@@ -521,7 +521,12 @@
 			if (MY_CLIENT->has_quit) return NETWORK_RECV_STATUS_MALFORMED_PACKET;
 
 		case NETWORK_GAME_PASSWORD:
-			ShowNetworkNeedPassword(type);
+			if (_login_pw == NULL) {
+				ShowNetworkNeedPassword(type);
+			} else {
+				SEND_COMMAND(PACKET_CLIENT_PASSWORD)(type, _login_pw);
+				_login_pw = NULL;
+			}
 			return NETWORK_RECV_STATUS_OKAY;
 
 		default: return NETWORK_RECV_STATUS_MALFORMED_PACKET;
Index: src/network/network_internal.h
===================================================================
--- src/network/network_internal.h	(revision 12594)
+++ src/network/network_internal.h	(working copy)
@@ -192,6 +192,8 @@
 VARDEF Year _network_restart_game_year;      // If this year is reached, the server automaticly restarts
 VARDEF uint8 _network_min_players;           // Minimum number of players for game to unpause
 
+VARDEF char *_login_pw; ///< login password from -p argument
+
 void NetworkTCPQueryServer(const char* host, unsigned short port);
 
 byte NetworkSpectatorCount();
Index: src/openttd.cpp
===================================================================
--- src/openttd.cpp	(revision 12594)
+++ src/openttd.cpp	(working copy)
@@ -151,6 +151,7 @@
 		"  -G seed             = Set random seed\n"
 #if defined(ENABLE_NETWORK)
 		"  -n [ip:port#player] = Start networkgame\n"
+		"  -p password         = Join password\n"
 		"  -D [ip][:port]      = Start dedicated server\n"
 		"  -l ip[:port]        = Redirect DEBUG()\n"
 #if !defined(__MORPHOS__) && !defined(__AMIGA__) && !defined(WIN32)
@@ -359,7 +360,7 @@
 	 *   a letter means: it accepts that param (e.g.: -h)
 	 *   a ':' behind it means: it need a param (e.g.: -m<driver>)
 	 *   a '::' behind it means: it can optional have a param (e.g.: -d<debug>) */
-	optformat = "m:s:v:b:hD::n::eit:d::r:g::G:c:xl:"
+	optformat = "m:s:v:b:hD::n::eit:d::r:g::G:c:xl:p:"
 #if !defined(__MORPHOS__) && !defined(__AMIGA__) && !defined(WIN32)
 		"f"
 #endif
@@ -398,6 +399,9 @@
 		case 'l':
 			debuglog_conn = mgo.opt;
 			break;
+		case 'p':
+			_login_pw = mgo.opt;
+			break;
 #endif /* ENABLE_NETWORK */
 		case 'r': ParseResolution(resolution, mgo.opt); break;
 		case 't': startyear = atoi(mgo.opt); break;