This was a bug in tekkit that is fixed when updating to 3.0.4
Block place event handling was not being shot out to plugins. That means all plugins running off of the event handler for the javaclass BlockPlaceEvent did not recieve data thus it was not protecting block placements...
I know this as i even made a test plugin to check for it on this one version of tekkit. I forget which one. But to fix it. You must update tekkit!