Registration in 2003 International Conference on Computational Science  is compulsory for at least one of the authors of the accepted papers. The registration is not currently open yet. You should check at:

Note also that the registration for the workshop is actually the registration for the whole ICCS'2003 conference. Therefore, you will have free access to all the workshops and activities related to this general conference. In addition, the whole set of proceedings will be included in the conference fees. 

Finally, note that the Technical Session chairman is only responsible of all the academic aspects of the papers (including the submission, reviewing and final selection, among others). For questions about registration, lodging, visa, flights, or any other question, please contact  ICCS' 2003 organizers.