qpopper mysql "sql query fetch row failed ()"

  I have just installed qpopper with the mysql patch on my CentOS server 
and am having a problem querying the database. I've had this working on 
various other linux servers without any problem. If I query the default 
database it works but if I query one of the virtual database it fails.

Qpopper version 4.0.18-mysql-0.16 (standalone)

When I telnet to the default database it works:
telnet localhost 110
popper[26256]: (v4.0.18-mysql-0.16) Servicing request from 
"server.domain.com" at 127.0.0.1+OK ready
User exampleuser
+OK Password required for exampleuser.
Pass examplepass
+OK exampleuser has 0 visible messages (0 hidden) in 0 octets

However, if I telnet to a virtual database it fails:
telnet localhost 110
popper[26256]: (v4.0.18-mysql-0.16) Servicing request from 
"server.domain.com" at 127.0.0.1+OK ready
User [email protected] 
<mailto:[email protected]>
<21>Sep 14 13:59:54 popper[25647]: [email protected] 
<mailto:[email protected]>: ERROR: sql query fetch row 
failed (). User may not exist+OK Password required for exampleuse.

The query seems to chop off the last letter of the UserId when I use 
@domain.com

Any advice would much be appreciated.

All the best
Fred

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