Index: core/src/test/java/quickfix/mina/message/FIXMessageDecoderTest.java
===================================================================
--- core/src/test/java/quickfix/mina/message/FIXMessageDecoderTest.java	(revision 46)
+++ core/src/test/java/quickfix/mina/message/FIXMessageDecoderTest.java	(revision 49)
@@ -348,7 +348,22 @@
 
     @Test 
     public void testMinaDemux() throws Exception {
-        DemuxingProtocolCodecFactory codecFactory = new DemuxingProtocolCodecFactory();
+        String message = "8=FIX.4.2\0019=12\00135=X\001108=30\00110=036\001";
+        
+        doTestMinaDemux(message);
+
+    }
+
+    @Test 
+    public void testMinaDemuxFixt() throws Exception {
+        String message = "8=FIXT.1.1\0019=12\00135=X\001108=30\00110=036\001";
+        
+        doTestMinaDemux(message);
+
+    }
+    
+   private void doTestMinaDemux(String message) throws Exception, UnsupportedEncodingException {
+      DemuxingProtocolCodecFactory codecFactory = new DemuxingProtocolCodecFactory();
         codecFactory.register(FIXMessageDecoder.class);
 
         ProtocolDecoder decoder = codecFactory.getDecoder();
@@ -359,7 +374,7 @@
         int count = 5;
         String data = "";
         for (int i = 0; i < count; i++) {
-            data += "8=FIX.4.2\0019=12\00135=X\001108=30\00110=036\001";
+            data += message;
         }
 
         for (int i = 1; i < data.length(); i++) {
@@ -379,9 +394,8 @@
             output.reset();
             buffer.clear();
         }
-
-    }
-
+   }
+    
     private void assertMessageFound(String data) throws ProtocolCodecException {
         assertMessageFound(data, 1);
     }
Index: core/src/main/java/quickfix/mina/message/FIXMessageDecoder.java
===================================================================
--- core/src/main/java/quickfix/mina/message/FIXMessageDecoder.java	(revision 46)
+++ core/src/main/java/quickfix/mina/message/FIXMessageDecoder.java	(revision 49)
@@ -123,7 +123,7 @@
         }
         if (messageCount > 0) {
             // Mina will compact the buffer because we can't detect a header
-            if (in.remaining() < minMaskLength(HEADER_PATTERN)) {
+            if (state == SEEKING_HEADER) {
                 position = 0;
             }
             return MessageDecoderResult.OK;
@@ -297,7 +297,8 @@
     }
 
     private static BufPos indexOf(ByteBuffer buffer, int position, byte[] data) {
-        for (int offset = position, limit = buffer.limit() - minMaskLength(data) + 1; offset < limit; offset++) {
+        int limit = buffer.limit() - minMaskLength(data) + 1;
+        for (int offset = position ; offset < limit; offset++) {
             int length;
             if (buffer.get(offset) == data[0] && (length = startsWith(buffer, offset, data)) > 0) {
                 return new BufPos(offset, length);
@@ -337,6 +338,10 @@
                 return -1;
             }
         }
+        if(dataOffset != data.length){
+           // when minMaskLength(data) != data.length we might run out of buffer before we run out of data
+           return -1;
+        }
         return bufferOffset - initOffset;
     }