Fix failing prefix detection of the "Re:subject" case (note the missing whitespace)
Fix failing prefix detection of the "Re:subject" case (note the missing whitespace)

svn path=/trunk/kdenetwork/kmail/; revision=177517

lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi