Is our SOA record right??

[Herv]

Hello, Earthlink is hosting our domain, and I've been questioning this
for a good two weeks, and I'm not getting anywhere with them.  In the
SOA, they have "localhost." as the primary server, but there's no A
record for localhost, and it's not in a fully qualified domain name. 
What problems could this cause?  At times we are not getting all of
our emails, it's very sporatic, and it may only be like 5-8 emails in
a day, but still would like this to be fixed.  This is what I got from
when I do a dig.

 
; <<>> DiG 2.1 <<>> @dns1.menandmice.is halurban.com SOA  
; (1 server found) 
;; res options: init recurs defnam dnsrch 
;; got answer: 
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 10 
;; flags: qr rd ra; Ques: 1, Ans: 1, Auth: 3, Addit: 2 
;; QUESTIONS: 
;; halurban.com, type = SOA, class = IN 
 
;; ANSWERS: 
halurban.com. 86400 SOA localhost. hostmaster.earthlink.net. ( 
 2004081901  serial  
 86400  refresh (1 day)  
 900  retry (15 mins)  
 2592000  expire (30 days)  
 86400 )  minimum (1 day)   
 
;; AUTHORITY RECORDS: 
halurban.com. 86400 NS dns3.earthlink.net.  
halurban.com. 86400 NS dns1.earthlink.net.  
halurban.com. 86400 NS dns2.earthlink.net.  
 
;; ADDITIONAL RECORDS: 
dns2.earthlink.net. 1790 A 207.217.77.12  
dns3.earthlink.net. 1792 A 207.217.120.13  
 
;; Total query time: 10047 msec 
;; FROM: us.mirror.menandmice.com to SERVER: default -- 0.0.0.0 
;; WHEN: Mon Aug 23 08:43:14 2004 
;; MSG SIZE sent: 30 rcvd: 188