how do you change directory on the remote server using jsftp in nodejs

Can anyone tell me how to change the directory on the remote server using jsftp in node js?

I have tried:

Ftp.raw.cd("subfolder",function(err, data) {
    ...

but I get an error:

TypeError: Object function () { [native code] } has no method 'cd'
...

Running console.log on Ftp.raw shows:

{ [Function]
  abor: [Function],
  pwd: [Function],
  cdup: [Function],
  feat: [Function],
  noop: [Function],
  quit: [Function],
  pasv: [Function],
  syst: [Function],
  cwd: [Function],
  dele: [Function],
  list: [Function],
  mdtm: [Function],
  mkd: [Function],
  mode: [Function],
  nlst: [Function],
  pass: [Function],
  retr: [Function],
  rmd: [Function],
  rnfr: [Function],
  rnto: [Function],
  site: [Function],
  stat: [Function],
  stor: [Function],
  type: [Function],
  user: [Function],
  xrmd: [Function],
  opts: [Function],
  chmod: [Function],
  size: [Function] }

The issue being that cd is not a valid function, hence the error. You should probably use Ftp.raw.cwd instead to set the current directory. If you wish to go up one level, the cdup function seems to be implemented for that purpose.