mode Z compression and idftp 9.0.19

Hello,

I would like to use mode Z compression with idftp 9 (9.0.19).
idftp transfertmode don't propose this mode

how do I have to proceed ?
Must I Compress file before send and decompress after received ?

for activate mode Z on my server ( filezilla server ), before send file,
I make that :

try
idftp1.sendCmd('MODE Z')
// mode Z enable on server
except
// mode Z disable
end;


thanks

jerome