1.4 Has just been released on Minecraft!
thats the good news,
the bad news is, Multiplay are currently updating Minecraft, so the server will not be supporting 1.4 until then,
i would advice DO NOT update your Minecraft until i reply to this post saying the server has been updated,
this could be a few hours, or a few days.
If you do update, you wont be able to play on our server till then, or any other server infact!
If you want to down-grade your Minecraft back to 1.3 till then, google for results,
Cheers.
http://forums.slap-gaming.com/viewtopic.php?f=28&t=156
Click link above if you need to downgrade!!!