it seems that nobody can upload inps using the regular default method for the time being. You need to use the alternate form that's linked from the Submit page by uploading your zipped inps to another site and then having it point there.
Yeah sometimes it works but most of the time it doesn't. If you don't have any other possibility to upload inps you might want to use Yahoo's Briefcase feature or some similar online file storage site, and upload your inps from there (using of course the alternative submission form like BBH said).
RESULTS
got something from that URL : length 8949 bytes
That doesn't look like a .zip file...
This is what I get when using the alternate form. http://tar.iwarp.com/zips
this is where my inps are.
They are ok, can't figure it out.
I want to send firebatl / 112750 / dos alpha69/ first place
These are the three I have tried so far , every day actually.
I get a different length every time.
I had the same trouble last year when ztnet was not accepting uploads.
The standard form still not working either.
I should just work on some more games to send for when it is fixed.
The third gives a 403 (Forbidden), with a message saying that data files must be on the same server as the one they are linked from. So in other words, you're screwed.