Index: core/src/test/java/org/apache/logging/log4j/core/appender/SMTPAppenderTest.java
===================================================================
--- core/src/test/java/org/apache/logging/log4j/core/appender/SMTPAppenderTest.java	(revision 1513588)
+++ core/src/test/java/org/apache/logging/log4j/core/appender/SMTPAppenderTest.java	(working copy)
@@ -16,6 +16,8 @@
  */
 package org.apache.logging.log4j.core.appender;
 
+import java.util.Iterator;
+
 import javax.mail.Address;
 import javax.mail.Message;
 import javax.mail.MessagingException;
@@ -146,10 +148,12 @@
         root.debug("Debug message #3");
         root.debug("Debug message #4");
         root.error("Error with exception", new RuntimeException("Exception message"));
+        root.error("Error message #2");
 
         server.stop();
-        assertTrue(server.getReceivedEmailSize() == 1);
-        final SmtpMessage email = (SmtpMessage) server.getReceivedEmail().next();
+        assertTrue(server.getReceivedEmailSize() == 2);
+        final Iterator messages = server.getReceivedEmail();
+        final SmtpMessage email = (SmtpMessage) messages.next();
 
         assertEquals("to@example.com", email.getHeaderValue("To"));
         assertEquals("cc@example.com", email.getHeaderValue("Cc"));
@@ -167,6 +171,13 @@
         assertTrue(body.contains("Error with exception"));
         assertTrue(body.contains("RuntimeException"));
         assertTrue(body.contains("Exception message"));
+        assertFalse(body.contains("Error message #2"));
+        
+        final SmtpMessage email2 = (SmtpMessage) messages.next();
+        final String body2 = email2.getBody();
+        assertFalse(body2.contains("Debug message #4"));
+        assertFalse(body2.contains("Error with exception"));
+        assertTrue(body2.contains("Error message #2"));
     }
 }
 
Index: core/src/main/java/org/apache/logging/log4j/core/net/SMTPManager.java
===================================================================
--- core/src/main/java/org/apache/logging/log4j/core/net/SMTPManager.java	(revision 1513588)
+++ core/src/main/java/org/apache/logging/log4j/core/net/SMTPManager.java	(working copy)
@@ -136,9 +136,6 @@
         }
         try {
             final LogEvent[] priorEvents = buffer.removeAll();
-            if (priorEvents == null || priorEvents.length == 0) {
-                return; // nothing to do, another thread already took all events
-            }
             final byte[] rawBytes = formatContentToBytes(priorEvents, appendEvent, layout);
 
             final String contentType = layout.getContentType();