[Dovecot] Some dovecot conf parameters

[Proskurin Kirill]

Hello all!
First of all - sorry for my english. :-)

Im working now on migration from cyrus to dovecot(v1.07). Everything 
work`s fine for now, but some parameters at dovecot conf a mystical for 
me. :-)

dovecot-ldap.conf:

user_attrs = mail
#,homeDirectory,,,,
user_filter = (&(objectClass=qmailUser)(mail=%u))
pass_attrs = mail,userPassword=password
pass_filter = (&(objectClass=qmailUser)(mail=%u))

What does this parameters mean? Im understand what mean a *_filter, but 
im do not understand a *_attrs.
Yes, im read a http://wiki.dovecot.org/AuthDatabase/LDAP
and http://wiki.dovecot.org/PasswordDatabase/ExtraFields

But don`t understand it. :-(

Ask you for help, or just say what im read this wiki again and again.

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Best regards,
	Proskurin Kirill