javax.activation.DataSource class not found

[Alan Snyder]

Trying to create a javax.mail.internet.MimeMessage, I get this error in release 144:

java.lang.ClassNotFoundException: javax.activation.DataSource
	at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:367)
	at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:186)
	at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:477)
	… 

Is this a known bug?

I cannot tell if it relates to JDK-8160373.