Need trimming/Toning advice

Ok, I am a 24 year old guy. I excercise daily (jog 2 miles in the afternoon, workout for 1.5-2 hours every night, and walk 4 miles after my workout). I have maintained a strict diet, and just recently started a high protein version of the south beach diet. Now with that in mind.

My problem is i am lean on 90% of my body, minus my lower back (love handles). I walk, do alot of core, workout my lower back twice a week and still cant seem to get it off. Any suggestions on a workout that focuses more on this area? i am at a loss and getting real frustrated.

What are the lower back exercises you are doing now when working out?

I mean the basic. Multiple deal lift sets. Sumo and normal grip. And then i do reverse sit-ups with moderate weight. Seems to hit my lower back with a good workout. I also do obliques twice a week.

You do twist crunches as well? Usually they are very effective (if one is consequent).