This error is related to typographical error i.e. there is some SPACE or invisible character in the command line. As of 22.03.2015, following command works fine:
c:\saprouter> sapgenpse -l c:\saprouter\sapcrypto.dll get_pse -v -a sha256WithRsaEncryption -s 2048 -r certreq -p local.pse "CN=...."
The CN=... should be changed to actual identifier for your saprouter.
Also, for Windows systems, in Regional Languages and Settings of Control Panel, make sure that keyboard is English (US)
Regards,
Bhagirath