The mailing list for listmasters using Sympa

[Thomas Berry <address@concealed>]

Sympa 5.3.4
Red Hat Enterprise Linux Version 3
running on an HP DL380 w/4GB RAM

 We have a very active mailing list server.  A weekly distribution is 
made to a list of about 7500 members who are self-subscribed, so the 
source of the email addresses is a SQL database (not the LDAP server).  
When a message is distributed to this list, all other distributions get 
held in the "distribute" spool until the weekly distribution is 
completed.  Sympa continues to receive and process messages (as can be 
seen by the accumulation of the messages in the distribute queue)  This 
wouldn't be a problem, but the distribution takes about 30 minutes to 
finish.

 We have sendmail installed locally on Sympa.  Sendmail is configured 
with a SMART host that is our outbound email system.  I don't see any 
load issues during the distribution.

 Is there a possibility that our Sympa installation maybe configured 
wrong for this situation?