When you first log on to the server, just type in the console :
rconpassword xxx
You won't need to type the password every time, but rcon before every command for sure.
Also, check out this thread -
http://www.alliedassault.com/phpBB2/vie ... p?t=144343
And just a note - you only need to type 'map'. (rcon map obj/obj_team1)