need help with 4 way circuit and motion switch

I contacted lutron and they sent me a wiring diagram for the 3 way and i understand how to put the switch in that circuit, the problem is i have a 4 way with an actual 4 way switch in the middle, that is where i need the motion sensing switch. the original switch has 4 wires 2 white on one side and 2 red on the other. I watched the video and that looks ok but if i dont have an actual black wire i am confused. 2 wires will have to be laid to my sensor switches blue wire, but which 2? i am assuming it would be the ones from the other 2 switches blue terminal (ma-as companion switches?) then which wires connect to my 2 black sensor switch wires? they sent me a wiring diagram but it shows how to wire the sensor switch up on one end but not exactly how to replace a 4 wire switch that is in the middle position? i also may have another 4 wire switch too if so will the ma-as switch replace 2 end 3 ways and 1 middle 4 way and the sensor switch replace the other middle 4 way?

It sounds like Lutron sent you the directions for using a mechanical 3-way switch with the sensor. That won't work in your application. See wiring diagram 5 on page 10 of the document below. Per note 4, the sensor can go in the middle.

http://www.lutron.com/TechnicalDocum...ary/369488.pdf

3-way switches are basically A/B switches. Power comes in on the 'common' at one end and goes out through traveler A or B. At the other end, power comes in on traveler A or B and goes out to the light (switch leg) via the 'common.' 4-way switches are magical devices that ensure that the travelers are connected. Sometimes you have A-A and B-B, sometimes A-B and B-A. White wires attached to the switch implies that both the power and the switch leg are at the same end. The electrician used the black wire to send power or the switch leg to the other end.

You will need 2 MA-AS companion switches. You will need to identify where the power is. With the power on and lights off, test for voltage at the common terminal (usually black) of the 3-way switches. From this point use the white wires to bring power in on the black screw and out to the next device on the brass screw. The first power-in wire should be black. At the 4-way you will need to determine which white wire is bringing power in and which goes to the next device. Connect all the red wires to the blue screws. You will have 2 reds connected to the one blue at the 4-way.