What to do when the blocks dissapear?

[Lureleif]

I've recently tried playing on my tekkit lite server with a friend of mine, And theres no problem with being able to enter the server. But when we try to place items that come with the mod (like a quarry, marble or a steam engine, ect.) they dissapear half a second later. Any idea on how to fix it?

Greatly appreciate it.

[Munaus]

that's a weird bug. Please post the issue on the Tracker, according to the Bug Report Template in the >Tracker Rules and Guidelines.