Aziz Jarrah wrote:
  Thanks for your assistance. I appears that I was
running openjdk instead
 of the sunjdk. I have since switched to the sunjdk and added the
 javamailer  mail.jar and activation.jar which I was missing before. This
 is the error I am seeing now.
 ERROR mailsender.MailSenderPlugin     - SendFailedException has occured.
 javax.mail.SendFailedException: Invalid Addresses;
   nested exception is:
         com.sun.mail.smtp.SMTPAddressFailedException: 550 5.1.1
 <null>... User unknown 
Yes, this is known and fixed in 1.9, please download
http://maven.xwiki.org/releases/com/xpn/xwiki/platform/plugins/xwiki-plugin…
and place it in the WEB-INF/lib folder, and remove the existing version
of this plugin.
--
Sergiu Dumitriu
http://purl.org/net/sergiu/