Although B<BerkeleyDB> is covered by the Perl license, the library it
makes use of, namely Berkeley DB, is not. Berkeley DB has its own
copyright and its own license. Please take the time to read it.
Here are few words taken from the Berkeley DB FAQ (at
F<http://www.oracle.com/technology/products/berkeley-db/db/index.html>) regarding the license:
Do I have to license DB to use it in Perl scripts?
No. The Berkeley DB license requires that software that uses
Berkeley DB be freely redistributable. In the case of Perl, that
software is Perl, and not your scripts. Any Perl scripts that you
write are your property, including scripts that make use of Berkeley
DB. Neither the Perl license nor the Berkeley DB license
place any restriction on what you may do with them.
If you are in any doubt about the license situation, contact either the
Berkeley DB authors or the author of BerkeleyDB.