Download of SirAdmin 1.0 for Mac was available from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The program lies within Communication Tools, more precisely E-mail.
The actual developer of this free software for Mac is Nigel Kersten. According to the results of the Google Safe Browsing check, the developer's site is safe. Despite this, we recommend checking the downloaded files with any free antivirus software.
From the developer:
SirAdmin is essentially a GUI replacement for cyradm, a command line tool that ships with the Cyrus IMAP server. SirAdmin allows you to locally or remotely administer your Cyrus IMAP server.
SirAdmin allows you to create, rename, delete, and reconstruct mailboxes, and also allows you to set Access Control Lists for IMAP mailboxes.
You may want to check out more Mac applications, such as SkypeMW, Zimbra Toaster or PageSender, which might be similar to SirAdmin.