R help - Jun 2008 - package tm, error with VectorSource

Hi,

the documentation for tm advertises the following:

 > docs <- c("This is a text.", "This another one.")
 > Corpus(VectorSource(docs))

but this doesn't work for me:

 > docs <- c("This is a text.", "This another one.")
 > Corpus(VectorSource(docs))

Corpus(VectorSource(docs))
Error: could not find function "VectorSource"
Error in Corpus(VectorSource(docs)) :
   error in evaluating the argument 'object' in selecting a method  
for function 'Corpus'


Is this a bug?

Thanks in advance