The majority of SBML development has been moved to github. Any issues should be filed there under the appropriate repository, i.e.
https://github.com/sbmlteam/libsbml/issues
https://github.com/sbmlteam/sbml-specifications/issues
https://github.com/sbmlteam/sbml-test-suite/issues
https://github.com/sbmlteam/sbml-org-website/issues/
Other repositories may be found in the 'sbmlteam' organization: