The sensitivity of a graphite rod is subject to the quality and quantity of the graphite. You do want a fast-action, stiff rod for calico fishing around rocks and kelp as mentioned. I bet yours is more sensitive than any 'glass rod though. I fish the shimano calcutta series too and am pretty stoked on them. If you want a ultra-sensitive rod, try a Loomis GL3 or IMX. They are what I use for freshwater bassing since the bites are sometimes very subtle. They do cost more though. You might be able to increase sensitivity by using a stiffer line or by how you hold the rod. Hold the foregrip ahead of the reel and rest the line between your index finger and thumb to feel bites better. Or, buy another rod :-)

Big Hammer Swimbaits-Hammerhead Jigheads
www.swimbait.com
Pro-Cure Scents
www.pro-cure.com