Growing up, I had that problem with my sister. We are not twins however, My sister was always a competitive type...tinged with a green streak of envy and jealousy. It caused friction all these years until adult hood, whereby she actually told me she was jealous of me. Who knows why, as we were raised the same. It is just her personality type.
That being said. Your girls are young...but still, every child needs help to ground them. My parents, would always emphasize that we were a "team" and that as siblings we are to protect and be there for each other always. I see that you treat them equally.... and that's good. Perhaps they need their "own" uniqueness and activities? The main thing is that you don't want "resentment" to be added to the pot. THAT is a hard nut to crack. I know, I dealt with that with my sibling.
I don't have any answer for you per say, just my own experience in dealing with that sort of situation in my life with my sibling. It's not easy. Perhaps, your twins are different in personality... and perhaps they both need different ways of being handled. I know it's not easy. Sorry I couldn't offer a specific thing. But my sister said she always felt like I was the "favorite" even though she was the "class president" type. Sometimes, a child just needs more and needs to be sure of themselves more, and needs more attention for their own individuality. Some kids are always trying to "prove" themselves too... and this can in turn be turned toward the other sibling in a negative way. Perhaps, have one-on-one time with each twin, separately. With help from Hubby of course. That is what my friend does, who has twins herself. Each child is unique and nurturing each is different.
Well, just some reflective ideas on things. Hope it helps... good luck,
~Susan
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