In bunnies, you can definitely get this pattern in both males and females. In fact, there’s a whole breed that only has the coloring you’re describing (though you can have bunnies of different breeds in that same color).
It sounds like your bunnies are harlequin. There are two varieties –
Japanese harliquin (I think this particular rabbit is actually the harlequin breed as well as the color): http://www.petplanet.co.uk/petplane…lequin.jpg
and Magpie harlequin (obviously not the harlequin breed, just the color, since this bun is a lop): http://sunshinebunnies.webs.com/Sun…lossom.JPG
You can also have a Japanese harlequin with white patches and it’s called tricolor. This color comes from crossing a regular harlequin colored bun with one that is “broken” - has white plus another color. The bun in my avatar is a broken black, for example. So a tricolor bun is just a broken harlequin, if that makes sense. This is the color that really looks like a calico cat: http://www.freewebs.com/jkhoppers/viking.jpg
I hope this helps! I’d love to see pictures of your buns – harlequin is my absolute favorite color. It’s just so unique.