TCPClient on webplayer crashes.

Hi. I recently tried to make client/server connection between Unity Webplayer and TCPListener server written in C#. The problem is when I start it, whole browser crashes (or when tested in Editor whole editor crashed) without any possibility to stop executing. The funny thing is logs say everything is OK.

 Platform assembly: C:\Users\Chlopaki\AppData\LocalLow\Unity\WebPlayer\player\Alpha3.x.x\Data\lib\CrossDomainPolicyParser.dll (this message is harmless)
 SocketPolicyClient1: Incoming GetPolicyStreamForIP
 SocketPolicyClient1: About to BeginConnect to 127.0.0.1:843
 SocketPolicyClient1: About to WaitOne
 SocketPolicyClient1: Socket connected

However when i change my TCPListener port to default for crossdomain-policy (843) client sends request to server for a policy. It receives nothing and it doesn't crash.

My crossdomain.xml looks like that:

 <?xml version="1.0"?>
 <cross-domain-policy>
 <allow-access-from domain="*" to-ports="500-1000"/>
 </cross-domain-policy>

Any idea what am i doing wrong?

PS. WWW Class requests works perfectly.