diff --git a/codec-smtp/src/main/java/io/netty/handler/codec/smtp/SmtpRequestEncoder.java b/codec-smtp/src/main/java/io/netty/handler/codec/smtp/SmtpRequestEncoder.java
index 1df357021c..1f479b41fa 100644
--- a/codec-smtp/src/main/java/io/netty/handler/codec/smtp/SmtpRequestEncoder.java
+++ b/codec-smtp/src/main/java/io/netty/handler/codec/smtp/SmtpRequestEncoder.java
@@ -47,13 +47,17 @@ public final class SmtpRequestEncoder extends MessageToMessageEncoder<Object> {
     @Override
     protected void encode(ChannelHandlerContext ctx, Object msg, List<Object> out) throws Exception {
         if (msg instanceof SmtpRequest) {
+            final SmtpRequest req = (SmtpRequest) msg;
             if (contentExpected) {
-                throw new IllegalStateException("SmtpContent expected");
+                if (req.command().equals(SmtpCommand.RSET)) {
+                    contentExpected = false;
+                } else {
+                    throw new IllegalStateException("SmtpContent expected");
+                }
             }
             boolean release = true;
             final ByteBuf buffer = ctx.alloc().buffer();
             try {
-                final SmtpRequest req = (SmtpRequest) msg;
                 req.command().encode(buffer);
                 writeParameters(req.parameters(), buffer);
                 buffer.writeBytes(CRLF);
diff --git a/codec-smtp/src/test/java/io/netty/handler/codec/smtp/SmtpRequestEncoderTest.java b/codec-smtp/src/test/java/io/netty/handler/codec/smtp/SmtpRequestEncoderTest.java
index 626bdfe671..7717b15139 100644
--- a/codec-smtp/src/test/java/io/netty/handler/codec/smtp/SmtpRequestEncoderTest.java
+++ b/codec-smtp/src/test/java/io/netty/handler/codec/smtp/SmtpRequestEncoderTest.java
@@ -18,6 +18,7 @@ package io.netty.handler.codec.smtp;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
 import io.netty.channel.embedded.EmbeddedChannel;
+import io.netty.handler.codec.EncoderException;
 import io.netty.util.CharsetUtil;
 import org.junit.Test;
 
@@ -85,6 +86,29 @@ public class SmtpRequestEncoderTest {
                 new DefaultLastSmtpContent(Unpooled.copiedBuffer("Test\r\n", CharsetUtil.US_ASCII))));
         assertTrue(channel.finish());
 
+        assertEquals("DATA\r\nSubject: Test\r\n\r\nTest\r\n.\r\n", getWrittenString(channel));
+    }
+
+    @Test(expected = EncoderException.class)
+    public void testThrowsIfContentExpected() {
+        EmbeddedChannel channel = new EmbeddedChannel(new SmtpRequestEncoder());
+        assertTrue(channel.writeOutbound(SmtpRequests.data()));
+        channel.writeOutbound(SmtpRequests.noop());
+    }
+
+    @Test
+    public void testRsetClearsContentExpectedFlag() {
+        EmbeddedChannel channel = new EmbeddedChannel(new SmtpRequestEncoder());
+
+        assertTrue(channel.writeOutbound(SmtpRequests.data()));
+        assertTrue(channel.writeOutbound(SmtpRequests.rset()));
+        assertTrue(channel.writeOutbound(SmtpRequests.noop()));
+        assertTrue(channel.finish());
+
+        assertEquals("DATA\r\nRSET\r\nNOOP\r\n", getWrittenString(channel));
+    }
+
+    private static String getWrittenString(EmbeddedChannel channel) {
         ByteBuf written = Unpooled.buffer();
 
         for (;;) {
@@ -95,8 +119,11 @@ public class SmtpRequestEncoderTest {
             written.writeBytes(buffer);
             buffer.release();
         }
-        assertEquals("DATA\r\nSubject: Test\r\n\r\nTest\r\n.\r\n", written.toString(CharsetUtil.US_ASCII));
+
+        String writtenString = written.toString(CharsetUtil.US_ASCII);
         written.release();
+
+        return writtenString;
     }
 
     private static void testEncode(SmtpRequest request, String expected) {