how to post twice?

[Anon]

A user can subscribe by posting a form on my site to a thirdparty website.

I wish to have a copy of his input, so then he press the submit button his information is stored in my database.

How do I redirect his input as a post to the thirdparty website without his knowledge?

[Anon]

have a single script that inputs all the info into your database and then sends all the form values to the 3rd party's server.

not too tough.

[Anon]

I have already figured that out, but how do I post the values?

I could redirect to the sites script with the values like wwww.3rdparty.com/?name=xxxx&address=xxxxx, but as i know It's not the same as posting the values?