We need a program which can generate virtual/fake visitors to a website.

The program should have following capabilities:

1. It needs to simulate that Visitor stays certain time on the site
2. The visitor needs to get logged by Javascript statistic software (i.e. pphlogger, Google Analytics)
IT'S VERY IMPORTANT THAT IT CAN INTERPRETE JAVASCRIPT!!!
3. It needs to be capable of sending up to 25.000 visitors a day
4. It needs to be capable of running from Win VPS Servers
5. Visitor Browser, OS, Screen resolution needs to be simulated
6. It should delete/terminate cookies/sessions after visit. (if a visitor comes from the same IP he needs to be counted again as new visitor.)
7. We should be able to use proxies if we wish through txt input

The developer should be able to start on it immediately.