[ADMB Users] Comparing non-nested models?

[Niklaus Kuehnis]

Is it possible to compare a zero-inflated poisson and a zero-inflated 
negative binomial model?

The models are:
a ~ b + factor(c) * d , random = ~ 1 | subject

The anova() output does not print the models, which looks strange:
anova(nb4a, nb4)
# Analysis of Variance Table
#
# Model 1: NULL
# Model 2: NULL
#   NoPar  LogLik Df -2logQ    P.value
# 1     7 -400.66
# 2     8 -388.10  1 25.122 5.3815e-07

vuong returns an error:
vuong(nb4, nb4a)
# Error in vuong(nb4, nb4a) :
#   could not extract dependent variables from models

Are there other commands to compare the two models?

Can I trust the anova() output?

TIA,
Niklaus