Arthritis and lifting?

Among a ton of other chronic conditions, I have mild rheumatoid arthritis. It affects my hands worst, and also knees, hips, shoulders, feet, ankles.

I wondered if there were other people out there who have arthritis (of any form - I also have osteo in me knees) who undertake a strength program? I've only just started this year, and have taken weights from 3kg dumbbells to 7kg/8kg (depending which I can get my mitts on at the gym). I have zero problems lifting 7kg in each hand for the first few reps - but then it's my hands that get sore to hold them, instead of my muscles. I push through of course, but end up with sore hands in order to get a good workout. The same happens when I row on the stationary rower, or use cable machines.

Does anyone else have a similar problem, and if so, how do you get around it? I put the weights down between sets (I do 8 reps in 3 sets for each type of exercise at the moment) for a few moments' break, but it would be great if I could manage more sets or exercise longer because I could hold the dumbbell. (I also use a 10kg kettlebell for swings and clean and press - same issue).

On a related-but-side note, OMG HOW GOOD ARE SQUATS. Not with a barbell (I haven't got the courage to go to the Big Boy side of the gym yet to use the rack - I do my weights in the free floor area next to cardio bunnies...) but weighted with a dumbbell/kettlebell like goblet squats etc. My knees are SO MUCH BETTER for building more strength in them. I also managed a two minute wall sit today for the first time in the history of this fat *kitten*. (And now this fat *kitten* is turning into a 'booty' - bigger but with more bounce, less wobble) All thanks to a squat program. I wonder if it would be possible to apply a similar exercise program for hands? Although I think my hands are more 'rheumy' and knees more 'osteo' which does affect how they flare up (knees constant-but-tolerableish, hands can be fine then flare into omg-I-can't-hold-a-pen in a few minutes flat sometimes).

So yes anyway, any fellow arthritis fitfats or generally anyone who might be able to suggest tips... now's your chance :)