[BioC] Problem with biomaRt update in R-2.15.1

[Eleni Christodoulou [guest]]

Dear Bioconductor experts,

I have been working with some Bioconductor packages in R14 which I was using in the past. I recently installed R15. I upgraded the Bioconductor installation using
source("http://bioconductor.org/biocLite.R")  and
biocLite("BiocUpgrade")

I got in my terminal:
Using Bioconductor version 2.11 (BiocInstaller 1.8.3), R version 2.15.
Old packages: 'biomaRt'
Update all/some/none? [a/s/n]: 

I answered a (all packages) in the last question. However, biomaRt could not be installed. Here is the error message that I received:
checking for xml2-config... no
Cannot find xml2-config
ERROR: configuration failed for package ‘XML’
* removing ‘/home/cellnet/elenic/R15packages/XML’
ERROR: dependency ‘XML’ is not available for package ‘biomaRt’
* removing ‘/home/cellnet/elenic/R15packages/biomaRt’

I thus cannot update biomaRt which is essential for my analysis. Could you provide me with some help on this?

Thank you very much,
E.C.



 -- output of sessionInfo(): 

R version 2.15.1 (2012-06-22)
Platform: x86_64-unknown-linux-gnu (64-bit)

locale:
 [1] LC_CTYPE=en_US.utf8       LC_NUMERIC=C             
 [3] LC_TIME=en_US.utf8        LC_COLLATE=en_US.utf8    
 [5] LC_MONETARY=en_US.utf8    LC_MESSAGES=en_US.utf8   
 [7] LC_PAPER=C                LC_NAME=C                
 [9] LC_ADDRESS=C              LC_TELEPHONE=C           
[11] LC_MEASUREMENT=en_US.utf8 LC_IDENTIFICATION=C      

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] plyr_1.8

loaded via a namespace (and not attached):
[1] tools_2.15.1


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