A bug-tracking system for SWIG is located at the University of Chicago. Bug reports can also be sent to swigbugs@swig.cs.uchicago.edu.
Please note that due to the volume of e-mail I receive, bug reports may not receive an immediate response (and in some cases, a response is not be sent until the bug is actually fixed). If you have an immediate problem, you may want to search the bug database or post a message to the SWIG mailing list instead.
However, with that said, if you have a bug or suggestion for improvement that you don't want me to forget, the bug database is the best place to put it. I often walk through the database when working on improvements.