Using NeroCMD.exe with Nero Express

Is there a switch command that will allow you to backup subdirectories using the nerocmd.exe command? I am attempting to use the following commands in a file called backup.bat:

“c:\Program files\Ahead\Nero\NeroCmd.exe” –write –drivename D –real –detect_non_empty_cdrw –create_iso_fs –iso Backup C:\backup\*.* –force_erase_cdrw –speed 10

For some Nero will not allow me to backup subdirectories within the target folder, only files. Does anyone know why?