I find it is not very easy to find a correct DNS configuration for jabber domains (but it's so easy!), therefore I show you my configuration.

In your zone file :

your.domain.tld.		A	YOUR-IP
_xmpp-client._tcp.domain.tld. 86400 IN   SRV     20 0 5222 your.domain.tld.
_xmpp-server._tcp.domain.tld. 86400 IN   SRV     20 0 5269.your.domain.tld.

Add +1 to your serial number and reload bind.