I am trying to follow the reddit api, as outlined here:

https://github.com/reddit/reddit/wiki/API

Logging in using curl is not a problem:

curl -d user=user -d passwd=pass -c Cookie.txt http://www.reddit.com/api/login

Which gives me a cookie, in which (I assume) contains my user mod-hash:

4029916%2C2010-04-30T22%3A51%3A52%2C1243925043100000000000000000000000000000

Next I am trying to post, using:

curl -d uh=4029916%2C2010-04-30T22%3A51%3A52%2C1243925043100000000000000000000000000000 -d sr=test -d title=test -d r=test -c Cookie.txt http://www.reddit.com/api/submit

However, I receiver an error:

[".error.USER_REQUIRED"]

Can someone explain what I have done incorrectly/how I can fix it?