Zero-inflated and proportional data

Yes..it is possible. You can do this in JAGS (or OpenBUGS). You can find 
JAGS code
for a beta GLM(M) in our 'Beginner's Guide to GLM and GLMM with R". 
Extension
to a zero inflated beta binomial can be done via the zero trick in JAGS. 
And you
will need to find the mean and variance of a zero inflated beta GLM.



Kind regards,

Alain Zuur