Form module

Hi all,
I must create a contact module, for a site, a little particular: the site propose services that are assigned to professionals chosen by the site administrator.
It would have to work this way: the customer write on a site and an email arrive to the administrator; he decides which professional assign the work to ( and send him the contact).
From that moment the professional and customer comunicates only by the site and on the site must stay the archive of the emails
 that they exchange (visible to the administrator).
What I would like is that the professional and the customer comunicate only by the mail to the site, no need to use username and password: it must be the site that manages coded mailboxes that are assigned to them but they don't have to be in contact in others ways and don't have to ask anything else to the customer.  
Does anyone of you know if there is a cms or script already ready or similar to this that I can modifiy?
Thank you for your suggestions

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Never seen birthdays gifts like these! (regalo di natale on italian or idee cadeau mariage on french), membrane osmosi inversa

Why would it matter? If you have a problem, press the "Report Abuse" button on the bottom of every page. I guess if you wanted to be compleatly anomus, you could turn off the cookis, and change your IP aderess; but I doubt you have that much time, or if it's not that much of a problem, you could just get over it.