[R] "command not found" from system() call in GUI with proper PATH

When running a system file from within R, I have just started to get a "command not found" error although my PATH seems to be properly set and I can run the same system file from the terminal. The program I am trying to run is 'fastsimcoal' and is in /usr/local/bin. I confirm this in the terminal

[R] Command not found

Dear R users, I am getting the following error anytime I try to open a vignette, e.g.: > vignette('frame',package='grid') sh: : command not found I am working with "R version 2.11.0 Under development (unstable) (2010-02-17 r51148)" installed on an OpenSuse 11.0 system. Thanks for your help Seb