OK - we are currently working on this same thing with my daughter's only recently tamed filly.
This is what we are doing. I asked the farrier if he had any better suggestions and he thought it was great what we were doing, just keep at it.
In the round pen where she can't get very far, she is rubbed all over with a long (20 foot) cotton rope unitl she is bored with it. Then startign with the front feet and at complete liberity, the rope is looped over her fetlock and pressure applied. If she takes a step or two away, it is fine, that is why the rope is so long. If the horse goes to panic, drop one side of the rope. As it is not tied on, it will come off - then start over.
Eventually, the pressure will cause the horse to pick up the foot. Praise and lots of love. Repeat, asking for a few seconds before you put it down. Praise and love, repeat, each time adding more time it is up in the air. You don't want to over do any one foot, about ten minutes working per foot is more than enough - less if the horse is stressed about it.
Do this with the back feet too. The rope keeps you out of kicking distance and a bit of tugging/kicking does not put you in danger. Do not react to this stuff. Just keep asking for the foot to be up and for longer periods of time. For the first session, five seconds is probably a great achievement for hte back feet.
Having the horse at liberty takes away a lot of the thought that they are being forced and makes them have to think - which I find gets faster results.
My daughter's filly has had four such sessions now and will hold the fronts up for about five minutes and the backs for about two minutes.