if tables have different collation

select v.domainacct, a.login, a.firstname afirst, v.firstname vfirst, a.lastname alast, v.lastname vlast –into ##temp from dbo.Vacation2011 v left outer join dbo.ADUserList a on (v.lastname = a.lastname COLLATE SQL_Latin1_General_CP1_CI_AS and v.firstname = a.firstname COLLATE SQL_Latin1_General_CP1_CI_AS)