I've found that babies usually do have prettysharp nails. You could just clip the very tip off to dullthem. They shouldn't be overly long yet.
I forget what breed you have- do they have normal length fur?With my guys (Polish, Dwarf Hotot, Dutch, and New Zealand), if I noticethat the nails are much longer than the fur it's usually time for atrim. Of if they're starting to curl under, it's past timefor a trim. With the white nailed rabbits, it's really easyfor me to see if the nail is much longer than the quick (anotherindication that they need trimming). You can use a flashlightto see the quick better in dark nails.