I Need Webmail On My Server (so admins on my site can access it)

Right now, if i go to the cpanel of my site, I can access webmail of any of the email addresses I have. Unfortunatly, I would prefer it if the administrators did not know the password to the cpanel. I want them to be able to access mail from 1 of the email accounts. I have tried letting all the admins access the account through their own cliants, but it became a mess, not knowing wich admins have responded to which emails, because most emails are hosted localy when received by cliants such as outlook. Then I had the idea of making one page, with webmail on it. Where all the admins can read email, and delete the ones that have been answered. I have tried different ones such as squirrelmail, but i can't seem to get them to work. I am not sure, but I think they are ment to be installed on the server, not installed on a personal computer then uploaded to the server via ftp.If anybody has an answer to get webmail to work, or has a different solution, i would love to hear it!!!Thanks!