Question Regarding XMPP Domain

We currently have a server setup in our site with an xmpp domain of abc.com. We set it up this way so that user could use their e-mail address as there jid. jimbob@abc.com I seems when configuring it in this manner it breaks the presence plugin and causes some other issues. WHat is the proper way to setup the server. I have seen references for using the FQDN, but didn’t want users to remember im.abc.com.

I have setup SRV records on abc.com to point to im.abc.com

If i setup the xmpp domain to be im.abc.com with authentication through LDAP can they still enter the login asjimbob@abc.com or will it need to be jimbob@im.abc.com?

Thanks in advance.

Lee