IdFTP: Pause upload

Hello,

is there an easy way to pause an upload with IdFTP? I don't want to
cancel and append the file since some ftp servers doesn't support it
(f.e. FTP.Size doesn't work on some server which is necessary to
detect the position from with the resume has to be started).

And: I still have the problem that sometimes the uploads just hangs
up, the entire program will freeze. I can wait a few hours and nothing
happens anymore.

Best regards,

Andy