Problem with maildirsmtp

Hi All, 

I am having problem with maildirsmtp....When I give the command it gives a 
553 error....
This is what happenns......when I give the following command.... 

root@anurodh:~# maildirsmtp ~alias/pppdir alias-ppp- neolinuxsolutions.com
maildirserial: info: new/1048321013.502.anurodh bounced: 202.71.150.112 
said: 553 sorry, that domain isn't in
my list of allowed rcpthosts (#5.7.1)
maildirserial: info: discarding new/1048321013.502.anurodh: triple bounce
maildirserial: info: new/1048462422.515.anurodh bounced: 202.71.150.112 
said: 553 sorry, that domain isn't in
my list of allowed rcpthosts (#5.7.1)
maildirserial: info: returned new/1048462422.515.anurodh: qp 522
root@anurodh:~# 

What I understand is that anyhow my domain is not allowed on the 
mailserver.......i.e, my domain doesn't have an entry in the rcpthosts file 
at the main mail-server.... 

Am I making a proper diagnosis..or is it some other problem...Is this a 
client side problem.....I am using qmail with daemontools and 
ucspitcp....and am using serialmail to send the mails... 

Pls help....
Regards,
Animesh