I think the MFFS Multitool is buggy. What worked for me (don't ask how) was I right clicked a mob. I also had to shift-right click a mob to get out of Encoder Mode.
Nope I got ccSensors working with Tekkit!!!!
http://www.minecraftforum.net/topic/1121555-125-cc133-ccsensors-adding-sensors-to-minecraft-now-with-smp/
Under Previous Releases Spoiler
Bukkit Version - By cloudy