Unbalanced ANOVA in R?

Hi all

I'm trying to complete a textbook example originally designed for SPSS
in R, and I therefore need to find out how to compute an unbalanced
ANOVA in R.

I did a search on the mailinglist archives an found a post by Prof.
Ripley saying one should use the lme function for (among other things)
unbalanced ANOVAs, but I have not been able to use this object.
My code gives me an error.. Why is that ?

aov(lme(DELAY ~ DOSE + TRIALS,data=epinuneq))
Error in getGroups.data.frame(dataMix, groups) : 
	Invalid formula for groups

Any ideas? How do I get an ANOVA computation that can handle uniqual
sampe sizes in R?

/Fredrik

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