Postfix long delivery delay when sending 5000+ mails

[Lox]

Hello,

I face a problem on my shared hosting server. I have a user that regularly
sends some newsletters to about 5000 recipients. When this happens, it
prevents other user from sending and receiving message for more than 12
hours.

There are many options in postfix so I am not sure which one to tune up to
prevent such an issue, can anyone advices me on that ?

Any advices on my postfix (attached) configuration is also greatly
appreciated...

Thanks in advance.

-- 
Lox
lox.dev at knc.nc
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.ubuntu.com/archives/ubuntu-server/attachments/20110413/c69d8f3c/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: postconf
Type: application/octet-stream
Size: 2147 bytes
Desc: not available
URL: <https://lists.ubuntu.com/archives/ubuntu-server/attachments/20110413/c69d8f3c/attachment.obj>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: master.cf
Type: application/octet-stream
Size: 2355 bytes
Desc: not available
URL: <https://lists.ubuntu.com/archives/ubuntu-server/attachments/20110413/c69d8f3c/attachment-0001.obj>