root@mail:/usr/src/qmail/qmail-1.03# cat conf-library
-L/home/vpopmail/lib -lvpopmail  -lcrypt
#-lcrypt -lz

# IF you use MYSQL add the libraries
#-lmysqlclient
# IF you use LDAP add the libraries
#-lldap -llber
# IF you use PGsql add the libraries
#-lpgsql
root@mail:/usr/src/qmail/qmail-1.03# cat conf-vpopmail
/home/vpopmail

The home directory of the vpopmail user
root@mail:/usr/src/qmail/qmail-1.03#