Multicast in Windows XP Professional

[cs02lk1]

Hi,
My name is Costas and I am facing a problem regarding multicasting.
I want run an application which forwards multicast data to Unicast clients and I am implementing it in JAVA.
I have aproblem because I believe that my laptop does not support multicast. Why I say that? Because a week ago I had installed Windows XP Home Edition as delivered fromHP on my laptop. VLC worked just fine by broadcasting a video on a multicast address and receiving it on a different window on the same machine.
I recently bought Windows XP Professional SP2 OEM and installed it and I started developing my application but my receiver would never get the data. I tried VLC and it happens the same thing. The window that sends the data shows that RTP packets are transmitted but the receiving window cannot receive anything.
Is there a way to find out if my PC supports mulitcast or IGMP?

My PC Configuration:
HP nx9420 laptop
Network Interfaces:
1. Intel PRO/Wireless (I have it disabled at the moment)
2. Broadcom NetXtreme Gigabit Ethernet
OS: Windows XP Professional SP2

Anything else that you think is relevant and want to know I can provide

Any help is really appreciated

Thank you

Costas