I am looking for a package that provides mathematical functions for the non-symmetrical (skewed) normal distribution and also the poisson and exponential distributions.

I originally looked at the [Colt](http://acs.lbl.gov/software/colt/) package but it does not provide the inverse cumulative function. 

So I changed to [Apache Commons Math3](http://commons.apache.org/math/) which provides a much more comprehensive set of functionality, including the inverse cumulative probability of all distributions.

However, now I hit a wall again because I need the Normal Distribution to be parametrized for a non symmetric shape (i.e. left part of the mean is different than the right part of the mean). Are you aware of any package that supports all the above?