[R-sig-ME] offset in glmmPQL

[Maarten de Groot]

Dear all,

I have a small question about including an offset value into a glmmPQL 
with a poisson distribution. I want to compare the number of songs of an 
animal between treatments. Because the experiment time is not always the 
same I want to include this as an offset in my formula 
("mod<-glmmPQL(nosongs~offset(experiment.time)+treatment,random=~1|block/malenr,family=poisson,data=mcrs)"). 


However R seems not to recognize the command"offset" when using a glmmPQL.

Hopefully some one can help me.

Kind regards,

Maarten