Beta binomial and Beta negative binomial

Hi,
I need Beta binomial and Beta negative binomial functions but in R there is
only SuppDists package which provide this distributions using a limited
parameter space of the generalized hypergeometric distribution (dghyper & Co.)
which provide a limited parameter space for Beta binomial and Beta negative
binomial functions (e.g. alpha + beta <1 in the Beta negative binomial).

I've done a checkout to R svn to seek the code for the implementation of
distribution functions (dbinom et al.) but I haven't succeed. I don't know how
difficult could be to implement Beta binomial and Beta negative binomial
functions having the PDF  and CDF functions but I'm interested in implementing
it. I have programming skills but I don't know much about R internals.

Where is the code? Can I implement these new functions inside stats
package following the
same patterns as other probability distributions?

Yours,

Joan Maspons
CREAF (Centre de Recerca Ecol?gica i Aplicacions Forestals)
Universitat Aut?noma de Barcelona, 08193 Bellaterra (Barcelona), Catalonia
Tel +34 93 581 2915 ? ? ? ? ? ?j.maspons at creaf.uab.cat
http://www.creaf.uab.cat