I need an experienced programmer with excellent php skills to code a mass bulk mailer with the following features:

1. Create a new php based professional GUI with support for HTML and Plain Text messaging

2. Support for email attachments

3. Unlimited email uploads

4. Multi threaded / Multi Processing

5. Sending emails only via external multipe SMTPs and Proxies . HTTPS, Socks 4 and authenticated Socks 5 should be supported.

6. Easy SMTP account setup with automatic SMTP settings detection

7. Automatic SMTP server switching and throtting to overcome email provider limits

8. Simple admin panel interface to create users acounts to use the mailer

9. Mailer user's interface should be username and password authenticated on the web server.

I want to make the mailer to support multiple SMTP servers and Proxy switching. The automatic SMTP switching , throttling and sending speed management is needed to overcome the limits imposed by email providers. When the current SMTP account fails due to provider's limitation, the mailer will pause it, and the next available SMTP account will be used. This scenario will repeat itself until all your messages will be delivered successfully.For example, gmail offers free accounts which can be used as multiple SMTP servers but because Gmail only allows 500 email sends per day, users can create multiple gmail accounts and then use these multiple SMTP servers in the mailer.

Also when users add a SMTP account in the Mailer, you just specify SMTP server host, user name and password. The other settings such as SSL/TLS and port number should be detected automatically.