Is the JavaMail API implementation completely free? Can I ship it along with my product?
Yes. The current release of the JavaMail API implementation, is completely free and you can include it in your product. This release includes IMAP, POP3, and SMTP providers as well. Please do read the license and ensure that you understand it. (The license is available after clicking the Download button on the download page.) The JavaBeans Activation Framework is also free for use under a similar license.