Securing EJB with legacy ldap realm does not work

javax.naming.NamingException: WFLYNAM0027: Failed instantiate InitialContextFactory com.sun.jndi.ldap.LdapCtxFactory from classloader ModuleClassLoader for Module "org.wildfly.extension.io" version 5.0.0.Final-redhat-20180517 from local module loader @2ea6137 (finder: local module finder @41ee392b (roots: /home/mchoma/Repos/tests-ldap-kerberos/tests/target/dist/jboss-eap/modules,/home/mchoma/Repos/tests-ldap-kerberos/tests/target/dist/jboss-eap/modules/system/layers/base)) [Root exception is java.lang.ClassNotFoundException: com.sun.jndi.ldap.LdapCtxFactory from [Module "org.wildfly.extension.io" version 5.0.0.Final-redhat-20180517 from local module loader @2ea6137 (finder: local module finder @41ee392b (roots: /home/mchoma/Repos/tests-ldap-kerberos/tests/target/dist/jboss-eap/modules,/home/mchoma/Repos/tests-ldap-kerberos/tests/target/dist/jboss-eap/modules/system/layers/base))]]

Thread [default task-1] (Suspended)	
	owns: AuthenticationTimeoutSaslServerFactory$DelegatingTimeoutSaslServer  (id=500)	
	UserLdapCallbackHandler.lambda$getPrincipalMapper$0(Principal) line: 143	
	2024198162.apply(Object) line: not available	
	712660640(Function<T,R>).lambda$andThen$1(Function, Object) line: 88	
	1508181426.apply(Object) line: not available	
	ServerAuthenticationContext.rewriteAll(Principal, Function<Principal,Principal>, Function<Principal,Principal>, Function<Principal,Principal>) line: 1114	
	ServerAuthenticationContext.assignName(SecurityIdentity, MechanismConfiguration, MechanismRealmConfiguration, Principal, Evidence, IdentityCredentials, IdentityCredentials, boolean) line: 1144	
	ServerAuthenticationContext$InitialState(ServerAuthenticationContext$UnassignedState).setPrincipal(Principal, boolean) line: 1691	
	ServerAuthenticationContext.setAuthenticationPrincipal(Principal, boolean) line: 408	
	ServerAuthenticationContext.setAuthenticationName(String, boolean) line: 382	
	ServerAuthenticationContext.setAuthenticationName(String) line: 366	
	ServerAuthenticationContext$1.handleOne(Callback[], int) line: 898	
	ServerAuthenticationContext$1.handle(Callback[]) line: 839	
	TrustManagerSaslServerFactory.lambda$createSaslServer$0(CallbackHandler, Callback[]) line: 96	
	1848118324.handle(Callback[]) line: not available	
	PlainSaslServer.evaluateResponse(byte[]) line: 117	
	AuthenticationCompleteCallbackSaslServerFactory$1.evaluateResponse(byte[]) line: 58	
	AuthenticationTimeoutSaslServerFactory$DelegatingTimeoutSaslServer.evaluateResponse(byte[]) line: 106	
	SecurityIdentitySaslServerFactory$1.evaluateResponse(byte[]) line: 59	
	SaslUtils.evaluateResponse(SaslServer, ByteBuffer) line: 245	
	SaslUtils.evaluateResponse(SaslServer, ByteBuffer, ByteBuffer) line: 217	
	ServerConnectionOpenListener$AuthStepRunnable.run() line: 486	
	EndpointImpl$TrackingExecutor.lambda$execute$0(Runnable) line: 926	
	1160617561.run() line: not available	
	ContextClassLoaderSavingRunnable.run() line: 35	
	EnhancedQueueExecutor.safeRun(Runnable) line: 1985	
	EnhancedQueueExecutor$ThreadBody.doRunTask(Runnable) line: 1487	
	EnhancedQueueExecutor$ThreadBody.run() line: 1349	
	Thread.run() line: 748