I don't think the technology is the problem. You will need to answer

  1. Is the team doing the design good?
  2. Is the design good (does it cater for concurrency, contention, redundancy, high load etc)
  3. Is the team doing the development good, organized and able to work as a team?
  4. Is there a project manager and a team lead?
  5. In light of the above is the remaining time realistic to do the work?
If the answer to any of these is no then it won't matter what language you use -- you're in trouble either way.

On Tue, Sep 1, 2009 at 3:08 PM, Glenn Sequeira <gsequeira@gmail.com> wrote:
On Tue, Sep 1, 2009 at 2:47 PM, Ogure Obunga<write2ogush@gmail.com> wrote:

> an approximate figure would be the number of persons querying the systems to
> see the progress of their cases, some dating back in the 80s to date. people
> in this case is a combination of the general public, lawyers, court staff.

I don't think you'll have a problem with PHP per se.

>From a presentation by Cal Hendersen (developer of Flickr which is a
PHP application)
[http://www.niallkennedy.com/blog/uploads/flickr_php.pdf], back in
2004 they were handling:

 ~25,000 DB transactions/second at peak
 ~1000 pages per second at peak

On a slightly related note, John Adams gave a great presentation at
the Velocity 2009 on the challenges of scaling a site (Twitter) to
serve millions of users.
[http://en.oreilly.com/velocity2009/public/schedule/detail/7479]