Server Crash, unknown error.

Recently my server has been plagued by this annoying error that crashes the server.

[LUA]
Crazy physics on [420][prop_physics] [Ang:-1.#IND00,1.#QNAN0,180.000000] [Pos:-1.#IND00,-1.#IND00,1.#QNAN0] - removing
[/LUA]

Now the only reason i’m asking for help is because i really can’t work out why this is happening and the error gives almost no real description so please help, any ideas why this is happening and how to fix it?

http://forum.facepunch.com/showthread.php?t=1269050

Holy crap thank you, so nice to know why this is happening.