@cyp: Please read FAQ:
How do I configure site, transfer and/or any other settings for which there are no script commands?

Is there anyway to script in a way to make WinSCP issue the keepalive command when in SFTP mode or is this something that can be added in an update, etc.? I find this program to be great but compared to others; filezilla, etc. it really is horrible at staying connected to servers with limits.

Brilliant, thanks!

This issue has been added to the tracker:
Issue 134 – Custom keepalive commands.

I find that, with some servers (particularly the ones I use on a regular basis) do not respond to WinSCP's keep-alive commands and constantly time out.

I would like to see an option to create custom keep-alive commands so that I can send keep-alives that the servers I connect to will actually recognize.

Thanks.