Possible bug in FTP accounts - ISPC probably not to blame
I have just setup some new sites (on the same client).
I have set the same password for 2 different FTP users for 2 different sites (let's say user FTP-A for site A and FTP-B for site B), but I gave both accounts the same password.
The funny thing is that logging in with user FTP-B led to site A.
After I changed the password of FTP-B, connection was properly made with site B.
So there seems to be a bug in the login process on the FTP server.
(I am using pure FTP from Falko's perfect server setup with Debian Lenny)
=> workaround: always give different FTP passwords for every single account.
=> possible todo for ISPC: make sure a password is not given out twice.
Now I remember that I was surprised that Plesk did not allow two accounts with identical passwords - this may be the cause.