在Quercus上安装WordPress - Java

Question

I'm trying to install WordPress on localhost (Ubuntu 18.04) Tomcat 9.0.13 server. I've installed Tomcat and Quercus successfully.

While following WordPress 5 minute install steps, on step-2 (http://localhost:8080/wp/wp-admin/install.php?step=2) it throws 500 - Internal Server Error:

com.caucho.quercus.QuercusModuleException: java.lang.NoClassDefFoundError: javax/activation/DataSource
    com.caucho.quercus.QuercusModuleException.create(QuercusModuleException.java:64)

# continued to a full page of stack trace

While looking at server log files I can say that the problem is caused by PHP mailer, while trying to send welcome email. At the end of log file:

# continued stack trace

at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.base/java.lang.Thread.run(Thread.java:844)
    at PHPMailer.postSend(/opt/tomcat/webapps/wp/wp-includes/class-phpmailer.php:1330)
    at .(/opt/tomcat/webapps/wp/wp-admin/install.php:291)

Can somebody help me finish WordPress installation with or without PHP mailer functionality enabled? Any help is highly appreciated.