multiplayer message "cant reach server"

when i click on multiplayer in the main menu it comes up with the list of servers i have saved and then under each of them it says "cant reach server"
its annoying because i cant play with my friends or anything until this is fixed plus the server we play on usually is still 1.5.2 and i cant get on any other servers that are 1.6.2 can you send me a link to download 1.5.2 until this bug gets fixed