1. Building

maven compile

You will need to manually install the java mail, activation and transaction jars using
mvn install:install-file -DgroupId=javax.activation -DartifactId=activation -Dversion=1.0.2 -Dfile=activation.jar -Dpackaging=jar -DgeneratePom=true 
mvn install:install-file -DgroupId=javamail -DartifactId=javamail -Dversion=1.3.2 -Dfile=mail.jar -Dpackaging=jar -DgeneratePom=true
mvn install:install-file -DgroupId=javax.transaction -DartifactId=jta -Dversion=1.0.1B -Dfile=jta.jar -Dpackaging=jar -DgeneratePom=true

2. Installing

2.1. Via Maven

2.2. WAR file