shQuote()function instead helped. Our thanks to the tireless R-on-Windows maintainer Uwe Ligges for an earlier heads-up about the problem. So another quick bug-fix release 0.7.10 is now in Debian and should be on CRAN some time tomorrow.
We also put two small improvements in, see the full NEWS entry for this release:
0.7.10 2010-03-15 o new class Rcpp::S4 whose constructor checks if the object is an S4 object o maximum number of templated arguments to the pairlist function, the DottedPair constructor, the Language constructor and the Pairlist constructor has been updated to 20 (was 5) and a script has been added to the source tree should we want to change it again o use shQuotes() to protect Windows path names (which may contain spaces)
As always, even fuller details are in Rcpp Changelog page and the Rcpp page which also leads to the downloads, the browseable doxygen docs and zip files of doxygen output for the standard formats. A local directory has source and documentation too. Questions, comments etc should go to the rcpp-devel mailing list off the R-Forge page