Using Kerberos as login module results in LoginException: unable to find LoginModule class

When using <login-module code="Kerberos" flag="required">, the following exception is thrown:

javax.security.auth.login.LoginException: unable to find LoginModule class: org.jboss.security.negotiation.KerberosLoginModule

When replacing the login module with the one provided by the JVM:

<login-module code="com.sun.security.auth.module.Krb5LoginModule" flag="required">

no exception is thrown and authentication works as expected.

The Kerberos login module works in Wildfly 8.2.0. It appears the class loading or something similar has changed in 9.x onwards to cause this to stop working.