R help - May 2003 - glmmPQL, NA/NaN/Inf in foreign function call (arg 3)

Dear all, 

I try to fit a glmmPQL on a huge data with 384189 individuals id=1:384189:
working in 1520 establishments est:1:1516. The minimum number of individuals
in every establishment is 30. 

This works for a subsample excluding establishemnet cells smaller than 100,
but fail when we include smaller cells: 


R> summary(glmmPQL(count ~
+      I( age-ave(age,est) )* ave(age,est) +
+      I( wom-ave(wom,est) )* ave(age,est) +
+      I( age-ave(age,est) )* ave(wom,est) +
+      I( wom-ave(wom,est) )* ave(wom,est) ,
+              random = ~ I( age-ave(age,est) ) +
+                        I( wom-ave(wom,est) ) | est,
+                                          family=quasipoisson,
+                                         data=mydata
iteration 1
Error in logLik.reStruct(object, conLin) :
       NA/NaN/Inf in foreign function call (arg 3)
R> 

Which function call "NA/NaN/Inf in foreign function call (arg 3)"
refers to?

thanks
mahmood arai 

http://www.ne.su.se/~ma