FTPs connection failed - error ".. certificate rejected by ChainVerifier"

Hi,

I wanna use the XI-File/FTP-Adapter to connect to our FTPs-Server.

We have to use Username/Password to connect to the FTPs-Server (it's an Ipswitch WS_FTP-Server) - using X.509 is not possible (it's another department administrating the FTPs-Server).

Now I get the error "Error: Message processing failed: iaik.security.ssl.SSLException: Server

certificate rejected by ChainVerifier".

The Crypto-Package is installed and is working - we tested it by connecting via https to SAP NetWeaver.

Do we need a certificate if we just use USER/PASSWORD-Connection (no X.509)?

Thanx a lot,

bye

Wolfgang