what's the correct format for setting per-user override quotas in a passwd-file?

in my "dovecot.conf", i've:

protocol imap {
	mail_plugins    = quota imap_quota
	mail_plugin_dir = /usr/local/dovecot-plugins/imap
	plugin {
		quota        = maildir:storage=10240 # 10 MB quota limit
	}

in my "imap_user_file", i've:

passdb passwd-file {
	args            = /etc/dovecot/imap_user_file
	...

i have:

user@mydomain.com:{PLAIN}testpass:::::: quota=maildir:storage=4096

on login to the user@mydomain.com, however, QUOTA on the account's mailboxes is reporting as the global default:

10240

something wrong in my user string, i s'pose ...

thanks,

richard

--

/"
\ / ASCII Ribbon Campaign X against HTML email, vCards / \ & micro$oft attachments

[GPG] OpenMacNews at gmail dot com fingerprint: 50C9 1C46 2F8F DE42 2EDB D460 95F7 DDBD 3671 08C6