[ND] a mail server and ND5

[NOHATA, Hiroyasu]

According to product feature document of ND5, it adds a mail server,
in addition to a web server, in DMZ.
What is supposed as communication interface between the mail server
and ND5?
And what is the purpose of adding a mail server to an application
server?  Does it support EDI based on MHS, for example?
Thank you for your input,
Nohata
 
a figure in product feature document of ND5:
             
F                   
F
Internet ---- i --- Web Server     i
         \   
r /            
\.   r
          \  
e                
\. e .
           \/                        
\
           /\
w                   
w  / ND 5
          /  
a                   
a /
         /   
l \              
./ l
Intranet ---- l --- Mail Server/   l