Que tal algo como
SELECT DISTINCT messages.fromid,
messages.readed,
messages.fromid,
messages.toid ,
members.id AS pid
FROM messages
INNER JOIN members
ON members.id = messages.fromid
WHERE messages.toid = ".$mid."
AND members.status = 7
AND messages.kreaded !='1'
AND messages.subject != 'readed'
ORDER BY messages.fromid ASC,
messages.id DESC
OU
SELECT DISTINCT messages.fromid,
messages.readed,
messages.fromid,
messages.toid ,
members.id AS pid
FROM messages
INNER JOIN members
ON members.id = messages.fromid
WHERE messages.toid = ".$mid."
AND members.status = 7
AND messages.kreaded !='1'
AND messages.subject != 'readed'
ORDER BY messages.fromid ASC,
messages.sendtime DESC
Em messages.fromid ASC o ASC é puramente sintaticamente, pois ORDER BY sem especificar ASC/DESC assume ASC.
SELECT *
FROM TABLE
ORDER BY COL ASC
é o mesmo que
SELECT *
FROM TABLE
ORDER BY COL