diff --git a/src/python/oftest/illegal_message.py b/src/python/oftest/illegal_message.py
new file mode 100644
index 0000000..0c6a878
--- /dev/null
+++ b/src/python/oftest/illegal_message.py
@@ -0,0 +1,108 @@
+"""
+Support an illegal message
+"""
+
+from cstruct import *
+
+ILLEGAL_MESSAGE_TYPE=217
+
+class illegal_message_type:
+    """
+    Wrapper class for illegal message
+
+    OpenFlow message header: length, version, xid, type
+    @arg length: The total length of the message
+    @arg version: The OpenFlow version (1)
+    @arg xid: The transaction ID
+    @arg type: The message type (OFPT_ECHO_REQUEST=2)
+
+    @arg data: Binary string following message members
+
+    The message type is set to "illegal" and the pack assert
+    check for the OF header is disabled
+    """
+
+    def __init__(self):
+        self.header = ofp_header()
+        self.header.type = ILLEGAL_MESSAGE_TYPE
+        self.data = ""
+
+    def pack(self):
+        """
+        Pack object into string
+
+        @return The packed string which can go on the wire
+
+        """
+        self.header.length = len(self)
+        packed = self.header.pack(assertstruct=False)
+
+        packed += self.data
+        return packed
+
+    def unpack(self, binary_string):
+        """
+        Unpack object from a binary string
+
+        @param binary_string The wire protocol byte string holding the object
+        represented as an array of bytes.
+        @return The remainder of binary_string that was not parsed.
+
+        """
+        binary_string = self.header.unpack(binary_string)
+
+        self.data = binary_string
+        binary_string = ''
+        return binary_string
+
+    def __len__(self):
+        """
+        Return the length of this object once packed into a string
+
+        @return An integer representing the number bytes in the packed
+        string.
+
+        """
+        length = OFP_HEADER_BYTES
+
+        length += len(self.data)
+        return length
+
+    def show(self, prefix=''):
+        """
+        Generate a string (with multiple lines) describing the contents
+        of the object in a readable manner
+
+        @param prefix Pre-pended at the beginning of each line.
+
+        """
+
+        outstr = prefix + 'illegal_message (' + \
+            str(ILLEGAL_MESSAGE_TYPE) + ')\n'
+        prefix += '  '
+        outstr += prefix + 'ofp header\n'
+        outstr += self.header.show(prefix + '  ')
+        outstr += prefix + 'data is of length ' + str(len(self.data)) + '\n'
+        return outstr
+
+    def __eq__(self, other):
+        """
+        Return True if self and other hold the same data
+
+        @param other Other object in comparison
+
+        """
+        if type(self) != type(other): return False
+        if not self.header.__eq__(other.header): return False
+
+        if self.data != other.data: return False
+        return True
+
+    def __ne__(self, other):
+        """
+        Return True if self and other do not hold the same data
+
+        @param other Other object in comparison
+
+        """
+        return not self.__eq__(other)