Mail Server Config test passes despite errors in logs

2016-09-23 23:16:58,998 ERROR [http-nio-8085-exec-15] [EmailService] Failed to send email to: asd@asd.com
com.atlassian.mail.MailException: com.sun.mail.util.MailConnectException: Couldn't connect to host, port: asd, 25; timeout 10000;
  nested exception is:
	java.net.UnknownHostException: asd
	at com.atlassian.mail.server.impl.SMTPMailServerImpl.sendWithMessageId(SMTPMailServerImpl.java:214)
	at com.atlassian.mail.server.impl.SMTPMailServerImpl.send(SMTPMailServerImpl.java:151)
	at com.atlassian.bamboo.mail.EmailService.sendEmailSynchronously(EmailService.java:140)
	at com.atlassian.bamboo.mail.BambooMailer.send(BambooMailer.java:84)
	at com.atlassian.bamboo.ww2.actions.admin.mail.ConfigureMailServer.testSMTPServer(ConfigureMailServer.java:190)
...
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
	at java.lang.Thread.run(Thread.java:745)
Caused by: com.sun.mail.util.MailConnectException: Couldn't connect to host, port: asd, 25; timeout 10000;
  nested exception is:
	java.net.UnknownHostException: asd
	at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:2053)
	at com.sun.mail.smtp.SMTPTransport.protocolConnect(SMTPTransport.java:697)
	at javax.mail.Service.connect(Service.java:386)
	at javax.mail.Service.connect(Service.java:245)
	at javax.mail.Service.connect(Service.java:194)
	at com.atlassian.mail.server.impl.SMTPMailServerImpl.sendWithMessageId(SMTPMailServerImpl.java:174)
	... 273 more
Caused by: java.net.UnknownHostException: asd
	at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:184)
	at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
	at java.net.Socket.connect(Socket.java:589)
	at com.sun.mail.util.SocketFetcher.createSocket(SocketFetcher.java:310)
	at com.sun.mail.util.SocketFetcher.getSocket(SocketFetcher.java:236)
	at com.sun.mail.smtp.SMTPTransport.openServer(SMTPTransport.java:2019)
	... 278 more