[BioC] GoSeq error!

[Emanuela]

Hi all, 


When creating pwf I encounter this type of message:
> pwf <- nullp(genes, "hg19", "ensGene")
Loading hg19 length data...
Error in qr.R(qrx) : 
  could not find symbol "..." in environment of the generic function

 I have tried to take a look into the matrix and it's basically composed of 
Ensembl IDs and 1-0 values accordingly to differentially 
and non differentially expressed genes.
> sessionInfo()
R version 2.15.2 (2012-10-26)
Platform: x86_64-apple-darwin9.8.0/x86_64 (64-bit)
locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8

Thanks!!!
Emanuela