diff --git a/SerializableMailMessage/SerializableAlternateView.cs b/SerializableMailMessage/SerializableAlternateView.cs
index 82950dd..ee929bc 100644
--- a/SerializableMailMessage/SerializableAlternateView.cs
+++ b/SerializableMailMessage/SerializableAlternateView.cs
@@ -35,6 +35,7 @@ private SerializableAlternateView(AlternateView view) {
 			ContentStream = new MemoryStream();
 			view.ContentStream.CopyTo(ContentStream);
 			view.ContentStream.Position = 0;
+			ContentStream.Position = 0;
 			ContentType = view.ContentType;
 			TransferEncoding = view.TransferEncoding;
 		}
diff --git a/SerializableMailMessage/SerializableContentType.cs b/SerializableMailMessage/SerializableContentType.cs
index 4076d77..bea9a8e 100644
--- a/SerializableMailMessage/SerializableContentType.cs
+++ b/SerializableMailMessage/SerializableContentType.cs
@@ -15,7 +15,8 @@ public static implicit operator ContentType(SerializableContentType contentType)
 			ct.MediaType = contentType.MediaType;
 			ct.Name = contentType.Name;
 			foreach (string k in contentType.Parameters.Keys)
-				ct.Parameters.Add(k, contentType.Parameters[k]);
+				if(ct.Parameters.ContainsKey(k) == false)
+					ct.Parameters.Add(k, contentType.Parameters[k]);
 			return ct;
 		}
 
@@ -32,7 +33,7 @@ private SerializableContentType(ContentType contentType) {
 			Name = contentType.Name;
 			Parameters = new StringDictionary();
 			foreach (string k in contentType.Parameters.Keys) {
-				if(contentType.Parameters.ContainsKey(k) == false)
+				if(Parameters.ContainsKey(k) == false)
 					Parameters.Add(k, contentType.Parameters[k]);
 			}
 		}