seed in nicta's rng lib in scala

I'm using NICTA's RNG library and I want my RNG to be deterministic in tests. So let's say I just want to make below code always true.

Rng.chooseint(0, 5).run.unsafePerformIO == 3 

But I cannot find any way to set a seed, and run method does not take any arguments. Can anybody help?