[R] Error in lsmeans function

[Tomosumi Haitani]

Dear members,

I would like to conduct nonparametric two way ANOVA (repeated 
measures) and post hoc test by using ARTool and lsmeans package.
I have the following data,

> x<-runif(120)
> A<-gl(3,40,labels=c("a1","a2","a3"))
> B<-gl(2,20,120,labels=c("b1","b2"))
> ID<-gl(20,1,120)
> data<-data.frame(ID,x,A,B)

Then, I use art function in the "ARTool" package,
> dataART<-art(x~A*B+(1|ID),data=data)

But when I use lsmeans function in "lsmeans" package for post hoc 
test, the next error is shown.
> lsmeans(artlm(dataART, "A"), pairwise ~ A)
NOTE: Results may be misleading due to involvement in interactions
$lsmeans
Error in format.default(nm[j], width = nchar(m[1, j]), just = "left") 
:
   4 arguments passed to .Internal(nchar) which requires 3

Would you mind telling me what is wrong?

Best Regards,