Statistical analysis of variance

Does anyone know if there is a matlab function for Mauchly's test of sphericity? I have seen a few options in the file exchange but I am not sure if one is better than the other. Ideally I would like to see a standard function added to the statistics toolbox, though if it is available I would consider buying another toolbox.

I would also like to know if there is any current way of dealing with heterogenous data? Ideally a combination of the Greenhouse-Geisser, the Huynh-Feldt, and the lower-bound would be optimal as it would allow selection of a test based on the output of Mauchly's test.

If these are currently available functions please can someone direct me to a guide/example so I can see how to implement it.

All help appreciated. Dan