the problem is execftp that send another 220 response after the user statement by the pc so the client think about a problem, you need to use a unthouched ps2ftpd irx (i'm doing my elf version but i have some problem with the upload of files) or use flashfxp which is quite flexible
ps2os betatester, ps2tools codev, hdldump frontend dev
6 sony mc w/ps2os 0.2.4, hdl, ps2rmp1.50,ps2mp3...
na+hd maxtor diamondmax 7200 120GB
PS2 SCPH-30004R V6 ÐM$3 V2 firm 2.4 B.4
PS2 SCPH-50003 V9 ÐM$4 PRO firm toxic os 0.1