cvan

Trim their claw will help.  And take some time to play with you cat, burn some of his energy.
I had the same problem before, so I get a hamster for the small cat, redirect her attention to other things, and let the old cat adjust.

I also use these "Soft Claw" on the small cat: http://www.drsfostersmith.com/product/prod_display.cfm?c=3261+20827+19945&pcatid=19945
they are not easy to glue on the cat, but will keep them safe for a long time after all the hard work.

cvan

sorry for the late reply.

How's you cats doing?  Does your kitty still very active?

My hamster is in a cage, or inside a running ball, so the cats never have a chance to touch it.  They enjoy watching the hamster running around and sometimes talk to it.
http://www.youtube.com/watch?v=4J-XtmWnNOM

now my 2 cats get along very well, they can sit / sleep / eat next to each other.  The older cat is the kung fu master now, and chase back the young cat.