Hosting a server and can't place mod objects. Turns to vanilla blocks

[xxxHitman21xxx]

I'm hosting a server and I got my friend to join. We are both on the same version of Technic and everything but when we try to place objects such as the launch pad or anything it disappears and gets replaced by a dirt block every time. This happens to almost all place-able mod objects. Please help?

Edited March 17, 2014 by xxxHitman21xxx

[xxxHitman21xxx]

Never mind got it. Launched Tekkit jar instead of Minecraft_Server.1.6.4 Jar