[c-nsp] Transfer via FTP on non-port 21 server possible?

[Jose]

Hi everyone.  I was wondering if it could be confirmed whether one could 
transfer an IOS image from an FTP to a router even though the server is 
running the FTP server on a port other than 21?  So far I've tried it on 
an 800 series router with no luck but it's an old IOS image and was 
wondering if the newer images (even on different platforms) would work.

Thanks.

Jose