I have 2 addresses specified in the "Email Notifications Recipients" field on the project "Configure"
screen. As the comment below the field says, I have space separated the addresses. At the end of a
build, however, I get his exception in the log:

javax.mail.internet.AddressException: Illegal whitespace in address in string ``foo@bar.com
baz@bar.com''
at javax.mail.internet.InternetAddress.checkAddress(InternetAddress.java:926)
at javax.mail.internet.InternetAddress.parse(InternetAddress.java:819)
at javax.mail.internet.InternetAddress.parse(InternetAddress.java:555)
at javax.mail.internet.InternetAddress.<init>(InternetAddress.java:91)
at hudson.tasks.MailSender.createEmptyMail(MailSender.java:238)
at hudson.tasks.MailSender.createBackToNormalMail(MailSender.java:114)
at hudson.tasks.MailSender.getMail(MailSender.java:104)
at hudson.tasks.MailSender.execute(MailSender.java:64)
at hudson.tasks.Mailer.perform(Mailer.java:54)
at hudson.model.Build$RunnerImpl.post(Build.java:135)
at hudson.model.Run.run(Run.java:562)
at hudson.model.Build.run(Build.java:99)
at hudson.model.Executor.run(Executor.java:61)