I'm inclined to agree with Graham. I'd say that virtue is a subcategory of skill, that a virtue is a skill that we consider especially meritorious, and that -- like any skill -- has to be "learned, practiced, perfected".
Another take on virtues from management guru Tom Peters (written, IIRC, in his last good book "The Pursuit of Wow", some time before he jumped the shark), was that it's the act of an instant to sign up for the program, but the act of a lifetime to make good on your promise. The "program" in his example was exercise, but I think you can substitute any virtue or good habit.
Both are helpful ways to look at patience (or any other virtue or skill). In American society we venerate "natural" talent (whatever that is), and as a consequence we excuse ourselves for not developing skills. "Oh, I'm just not artistic/good at math/able to handle conflict/patient/whatever" places the matter out of our hands and excuses us from developing to whatever degree we can.