If we may believe our colleagues of Eurosong.be, the rules for the Eurovision Song Contest 2004 include that performers can't perform for more than one country. The Flemish TV1-programme manager Steve De Coninck-De Boeck told that to Eurosong.be.
Last year, the Dutch entrant Esther Hart also had a song in the British preselection but she withdrawled later. Ich Troje, the Polish entry of 2003, also had a song in the German national final. Now the European Broadcasting Union (EBU) wants to avoid such situations in the future.
The rules for the Eurovision Song Contest 2004 are almost ready and will soon be presented by the EBU.