I have enabled your contact form plugin developed by acrylian and sbillard. That worked fine. However a small weak point in that script is that the message sender can see the admin's email after he gets the copy of his question.
I have my domain based email for my zenphoto admin account of my website (such as admin@mysite.com). I checked this contact form with my yahoo mail address. However, when i receive the copy of my message i could see my admin email address in "to:" field. It means whenever a user sends a message via your contact form, the admin's email address is visible to that user. Any suggestions to fix this problem?
Thanks.

Is that the mail address you provided in the plugin's options?

Yes, I have provided my admin account's email in that option page.

Well, the contact form sends an email to the sender as well and that is send from the mail you entered. There are also fields on the two mail plugins you can choose to use from.

You could make your own version of that plugin. Change the call on zp_mail to BCC the mailing list rather than set it as the "to" address.