to Jeff: I keep a lot (7 to 10 per cage) of my klemmeri babies together without any problems.
to Peter: I just saw this thread. Some klemmeri males are much more aggressive than others. While I never had any bigger aggression problems with most of my males, one of them actually killed a female a couple of years ago. This year I tried to put him with four different females and he attacked all of them. And it wasn't just breeding behaviour, it was pure aggression, as he just wouldn't stop attacking them. Now I separated him and he'll have to spend the rest of his life alone, as I don't intend to use him for breeding anymore.
On the other hand my oldest klemmeri male is the friendliest male I've seen, but also the most shy.
In your case, it could also be a reaction to moving them to a new terrarium.
The male comes to a new territory and gets all territorial, even towards a female.
Sometimes it helps to put the female in a new terrarium a few days/a week before the male so she can establish her territory there.
If the aggression between your pair continues, I would remove the male from the cage, let the female recover for a few weeks and only then return the male back to the cage.
Maybe also clean and rearrange the terrarium after you take the male out, so he won't recognize it when he comes back.
I hope this helps.
Regards, Matjaz