one thing that *works* for me in this case is an app called httport from h**p://www.htthost.com

i am behind a proxy which allows me port 21 for ftping and nothing else.

with httport started i point my flashfxp (this is what u should use too) to the desired ftp with:

"127.0.0.1 port 1080" set as socks proxy. this setting lets the ftp-client connect via httport. httport connects to its own server htthost.com, from there u get directed to the desired server.

disadvantages:
-u can get instantly fired
-its not secure as there is a 3rd party server in the line
-slow (10kb over all, while i could have 250kb here at work)
-gets disconnected often

BUT

advantages:
-u can access servers u could never have accessed before

genius