Postfix user at domain splitting

[Ricardo Branco]

I have been trying looking though all the wiki documents to setup LMTP.
It now seems to all be connected except that it keeps saying that the 
user is not recognised when postfix sends to LMTP, it sends the full 
recipent email address but seems that on the dovecot side it is unable 
to work with this.
I have checked the userdb and made sure its using %n but alas it still 
does not work.
Currently ive had to revert to using LDA as it works fine with that but 
i still dont know how as the postfix config variable $RECIPIENT is the 
full email address and does not seem to matter to LDA.