Possible items bug?

[Jwoolner]

Hi,

This is my first post on these forums so take it easy =]

Basically ive been playing Tekkit for a week odd now, and ive got a really annoying bug. If i try to put items from inventory to use-able bar or to a chest, it throws the items on the floor.

Its also doing it now when i try to add items into construction blocks for instance adding supports blocks into a deployer or uranium into reactor.

At first i just played on but now its really irritating. If anyone could offer any help id be really appreciative of that.