Checkpoint FW-1 and "ftp missing newline char" attack

Howdy.

I'm trying to log in to a customer's ftp server from an AIX 5.3 box behind FW-1. This is eventually going to be a cron job, but right now I'm trying it manually for testing purposes.

I *have* to use passive mode.

Logging in defaults to active. No problem cding, lsing, getting, etc. Then I issue the passive command, after which any attempt to use the data port completely hangs the session.

Checking SmartView Tracker says that the firewall rejected the data request due to an 'ftp missing newline char' attack, and subsequent packets get dropped because they're out of state.

The admin at the customer site swears up and down that he's got passive mode enabled and the high ports open to me on his end. I've tried logging in to both his AS/400 and his MS box with the same results.

Anybody have any ideas?

Thanks.

I should probably add that ncftp, which apparently defaults to passive mode for data transfer, hangs in the same way as the normal client.