Output directory empty when invoked from command line

I excecuted the following commands being in flex-command-line directory

java -Xmx256m -jar flex-pmd-command-line-1.0.RC3.jar

java -Xmx256m -jar flex-pmd-command-line-1.0.RC3.jar -s "C:\Documents and Settings\mmkrishna\My Documents\Flex Builder 3\SchoolWebsite\src" -o "C:\Documents and Settings\mmkrishna\Desktop\OPDir" . -r custom_ruleset.xml

java -Xmx256m -jar flex-pmd-command-line-1.0.RC3.jar -s C:\Documents and Settings\mmkrishna\My Documents\Flex Builder 3\SchoolWebsite\src -o "C:\Documents and Settings\mmkrishna\Desktop\OPDir"

the output directory is empty when i checked .. no pmd.xml created.

whats the problem exactly

thannks in advance

aditya