diff --git a/mailnews/mime/public/nsIMimeHeaderConverter.h b/mailnews/mime/public/nsIMimeHeaderConverter.h
deleted file mode 100644
index d254c4a9941b..000000000000
--- a/mailnews/mime/public/nsIMimeHeaderConverter.h
+++ /dev/null
@@ -1,72 +0,0 @@
-/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
- *
- * The contents of this file are subject to the Netscape Public License
- * Version 1.0 (the "NPL"); you may not use this file except in
- * compliance with the NPL.  You may obtain a copy of the NPL at
- * http://www.mozilla.org/NPL/
- *
- * Software distributed under the NPL is distributed on an "AS IS" basis,
- * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
- * for the specific language governing rights and limitations under the
- * NPL.
- *
- * The Initial Developer of this code under the NPL is Netscape
- * Communications Corporation.  Portions created by Netscape are
- * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
- * Reserved.
- */
- 
-/*
- * This interface allows any module to access the encoder/decoder 
- * routines for RFC822 headers. This will allow any mail/news module
- * to call on these routines.
- */
-#ifndef nsIMimeHeaderConverter_h_
-#define nsIMimeHeaderConverter_h_
-
-#include "prtypes.h"
-#include "nsString.h"
-
-// {866A1E11-D0B9-11d2-B373-525400E2D63A}
-#define NS_MIME_HEADER_CONVERTER_CID   \
-        { 0x866a1e11, 0xd0b9, 0x11d2,         \
-        { 0xb3, 0x73, 0x52, 0x54, 0x0, 0xe2, 0xd6, 0x3a } };
-
-// {C09EDB23-B7AF-11d2-B35E-525400E2D63A}
-#define NS_IMIME_HEADER_CONVERTER_IID \
-      { 0xfb953da, 0xd0b5, 0x11d2,   \
-      { 0xb3, 0x73, 0x52, 0x54, 0x0, 0xe2, 0xd6, 0x3a } };
-
-// default line length for calling the encoder
-#define kMIME_ENCODED_WORD_SIZE       72 
-
-// Max length of charset name. 
-#define kMAX_CSNAME                   64 
-
-class nsIMimeHeaderConverter : public nsISupports {
-public: 
-  static const nsIID& GetIID() { static nsIID iid = NS_IMIME_HEADER_CONVERTER_IID; return iid; }
-
-  // These methods are all implemented by libmime to be used by 
-  // modules that need to encode/decode mail headers
-
-  // Decode routine
-  NS_IMETHOD DecodeMimePartIIStr(const char *header, 
-                                 char       *charset, 
-                                 char **decodedString) = 0;
-
-  // Decode routine (also converts output to unicode)
-  NS_IMETHOD DecodeMimePartIIStr(const nsString& header, 
-                                 nsString& charset, 
-                                 nsString& decodedString) = 0;
-
-  // Encode routine
-  NS_IMETHOD EncodeMimePartIIStr(const char    *header, 
-                                 const char    *mailCharset, 
-                                 const PRInt32 encodedWordSize, 
-                                 char          **encodedString) = 0;
-}; 
-
-#endif /* nsIMimeHeaderConverter_h_ */
-
-