Anonymous blog posting script

I need a script or software that makes it possible for people to post on multiple blogs without them knowing the username or password. The blogs are on different platforms, All blogs require certain fields, like url, name, ect. Some require to enter Captcha. The script or software should be easy to use and easy to implement on a website. I also need to be able to add more urls, usernames and passwords to the list of URL's for submission at any time. see example and more explication on the attached file