I'm not ready to commit it yet, and it's likely to have some changes, but I've whipped up a conversion of the CERN JET distribution library for MASON. It's modified so as (I think) to be serializable, use the MersenneTwisterFast class, and fit in the MASON distribution tree (as sim/util/distribution/). If you're interested, I have an early testing version here: http://cs.gmu.edu/~sean/temp/distribution.zip Tell me what you think. Sean