Union af to select sætninger

Jeg for følgende fejl når jeg prøver at benytte union

Illegal mix of collations  for operation 'UNION' Error 1271

min forspørgelse:
select 'out',CONCAT('0',q.prefix), qt.name AS prefix
from qos_digit_list q, qos_digit_provider qp, qos_digit_type qt
    where q.type = qt.id
    and q.provider = qp.id
union
select 'in' as one ,u.extn as two, u.login as three from qos_users u;

Hvad kan være galt det virker når jeg kun henter fra den ene tabel (qos_digit_list), men det lader ikke til at mine joins virker sammen med union, jeg har prøvet at oprette et view for at se hvad der sker men samme fejl opstår... !!!

tabeller
------------------------------------------------
CREATE TABLE `qos_digit_list` (
  `prefix` varchar(32) collate latin1_danish_ci NOT NULL default '0',
  `type` int(10) unsigned NOT NULL default '0',
  `provider` int(10) unsigned NOT NULL default '0',
  PRIMARY KEY  (`prefix`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 COLLATE=latin1_danish_ci;

CREATE TABLE `qos_digit_provider` (
  `id` int(10) unsigned NOT NULL auto_increment,
  `Name` varchar(45) collate latin1_danish_ci NOT NULL default '',
  PRIMARY KEY  (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 COLLATE=latin1_danish_ci;

CREATE TABLE `qos_digit_type` (
  `id` int(10) unsigned NOT NULL auto_increment,
  `Name` varchar(80) collate latin1_danish_ci NOT NULL default '',
  PRIMARY KEY  (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 COLLATE=latin1_danish_ci;

CREATE TABLE `qos_users` (
  `extn` int(10) unsigned NOT NULL default '0',
  `login` varchar(45) character set latin1 NOT NULL default '',
  `password` varchar(12) character set latin1 NOT NULL default '',
  `phonetype` int(10) unsigned NOT NULL default '0',
  `fullname` varchar(45) character set latin1 NOT NULL default '',
  `email` varchar(45) character set latin1 NOT NULL default '',
  `headset` tinyint(1) default NULL,
  `IP` varchar(45) character set latin1 default NULL,
  `location` int(10) unsigned NOT NULL default '0',
  PRIMARY KEY  (`extn`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1 COLLATE=latin1_danish_ci;