Help on Security Sandbox of the Webplayer

Hi, I am updating my old 2.6 project to 3.3. In my project, I used Smartfox's unity-plugin to connect to one smartfox server. Now after updated to 3.3, within webplayer mode, it cant connect to my server! I have tested in "PC and Mac Standalone", it works, So the only difference comes from using "webplayer" mode. I have done some study and found it has this "security sandbox" feature now, which is new to me, and to my project. So if any friend here has similar experience with me, can you pls give me some hint about this?? Thanks a lot!