R help - Jul 2011 - example for plot.compare.datasets() in package rioja fails

I'm using rioja 0.5-6 with R 2.12.1 / x86_64-pc-linux-gnu on 
Kubuntu 11.04.

     When I run this example from the rioja reference manual:

library(rioja)
# compare diatom data from core from Round Loch of Glenhead
# with SWAP surface sample dataset
data(RLGH)
data(SWAP)
result <- compare.datasets(RLGH$spec, SWAP$spec)
result
#visualise the comparison
plot.compare.datasets(result)

     Everything runs fine except for plot.compare.datsets() which gives 
the error:

Error in dim(x) : 'x' is missing
Calls: plot.compare.datasets -> nrow
Execution halted

     Any ideas?


Jason
===========

I'm using rioja 0.5-6 with R 2.12.1 / x86_64-pc-linux-gnu on 
Kubuntu 11.04.

     When I run this example from the rioja reference manual:

library(rioja)
# compare diatom data from core from Round Loch of Glenhead
# with SWAP surface sample dataset
data(RLGH)
data(SWAP)
result <- compare.datasets(RLGH$spec, SWAP$spec)
result
#visualise the comparison
plot.compare.datasets(result)

     Everything runs fine except for plot.compare.datsets() which gives 
the error:

Error in dim(x) : 'x' is missing
Calls: plot.compare.datasets -> nrow
Execution halted

     Any ideas?


Jason
===========