What am I missing? MX question

[steve]

localhost.mysite.com.   IN  A  127.0.0.1


mysite.com.       IN  A  xxx.xxx.73.26
mail.mysite.com. IN A xxx.xxx.73.27
www.mysite.com.    IN  CNAME mysite.com.

; global MX records for unspecified members of the zone
*.mysite.com.     IN  MX  10  mail.mysite.com. ;GLOBALOK

; MX records for email addressed to the zone itself
 *.mysite.com.       IN  MX  10  mail.mysite.com. ;EXTREF

E-mail sent from someone in the domain to someone else in the domain
seem to work.
E-mail sent from the domain to outside the domain work.
Mail sent from outside the domain to the domain bounces with 550
<someone at mysite.com>... Host unknown (Name server: mysite.com: host not
found).