diff --git a/src/common/buffer.cc b/src/common/buffer.cc
index e725ecd2a..2c64f8920 100644
--- a/src/common/buffer.cc
+++ b/src/common/buffer.cc
@@ -655,6 +655,14 @@ BufferTest::RunTests (void)
   i.Prev (1);
   i.WriteU8 (1, 1);
 
+  buffer = Buffer (6);
+  buffer.AddAtStart (3);
+  buffer.RemoveAtEnd (8);
+  buffer.AddAtEnd (4);
+  i = buffer.End ();
+  i.Prev (4);
+  i.WriteU8 (1, 4);
+
   return ok;
 }
 
diff --git a/src/common/buffer.h b/src/common/buffer.h
index 500e11f7c..4986d4998 100644
--- a/src/common/buffer.h
+++ b/src/common/buffer.h
@@ -522,7 +522,8 @@ Buffer::Iterator::GetIndex (uint32_t n)
   NS_ASSERT ( 
       (m_current + n <= m_dataEnd) &&
       ((m_current + n <= m_zeroStart) ||
-       (m_current >= m_zeroEnd))
+       (m_current >= m_zeroEnd) ||
+       m_zeroStart == m_zeroEnd)
       );
   uint32_t index;
   if (m_current < m_zeroStart)