Zippy Lipo question

For those who have Zippy lipos, have you noticed that they end up charging all the way to 4.25v per cell? For some strange reason, my little 1000mah 15C 3s zippy pack did this, and the charger has NEVER done this on any of my other two lipos which are 2s (Trinity and Apogee).

Is this normal for the zippys? There's no swelling at all, and the lipos don't even get above room temperature. So I'm wondering what the deal is.

Thanks guys.