I have been trying to get message relaying to work but nothing I do will help. I've been following the instructions on this page: ZimbraMtaMyNetworks - Zimbra :: Wiki but I keep getting an LDAP error 17 and saying something about a problem with the ATTR.

Here is my goal:
I have a server in which I use to host my website(s). I use to have the mail server configured there but about a year ago I decided to setup ZCS and started using ZCS for all of my emailing. My server is running frameworks (ie. Joomla and other programs like bamboo invoices) and these systems need to send out emails. I have entered in my SMTP details into the configuration files of said frameworks and scripts but the messages are not being delivered.

Upon further investigation into mail.err I found that there were multiple messages where it was saying that Relay Access Denied. So I naturally started googling to find the solution which led me to the above mentioned article. However I cannot get the solution to work.

Can someone please help me? Also the log files are stating client host unknown and listing my IP address for my other server (the one with the frameworks trying to send the messages).

Ultimately I would like to set it up so that I (or any of the users on the server) can configure their mail clients to use ZCS as their SMTP server from any where (i.e. their home, phone, server, etc).

At the same time I would like to reduce the possibilty of someone being able to hack into their email accounts and send thousands of spam messages from their accounts too.

Could someone please help me with this?