java.lang.NoClassDefFoundError: javax/mail/MessagingException unsolved

Also with the 1.4.3 version there is no longer an artifact id called mail. If you want to use 1.4.3 you should use this dependency

<dependency>
    <groupId>javax.mail</groupId>
    <artifactId>mailapi</artifactId>
    <version>1.4.3</version>
</dependency>

You should add the jar to the server Tomcat.

1. Open launch configuration

   

2. Add external jar (look for your email jar)

   

the javax/mail/MessagingException already exists in version 1.4. So I guess this is just an assembly issue within the IDE. Refreshing the pom dependencies and checking the artifact the IDE builds up should be sufficient.