see http://pastebin.com/2yQGiMYU
Maybe the problem has been solved. This's Railcraft 9.2.2.0.
When join the server again the same crash happened again, at the time I logged in.
May it be the bug of int "facing"?

Some other players in the server which I play also reported this bug. It causes a lot of crashes.

It should be impossible for the facing to be ForgeDirection.Unknown. Perhaps a corrupted tile entity.

Thank you!