Problems downloading PDK ,Please help me out .

I have ben trying to download the trial version of PDK ( Portal Development Kit ) , for sometime now , but it always says ,

Error 504 - Proxy Error: unable to open data connection for the FTP Server at ftp://ftp.sap.com/pub/sdn/devkits/PDK/PDK_EP6.0_60_2_2.zip.

Explanation: The proxy server did not receive any data from the FTP server, perhaps the connection was closed.

Action: Please retry your request.

URL: ftp://ftp.sap.com/pub/sdn/devkits/PDK/PDK_EP6.0_60_2_2.zip