Currently I am using Maya 2010 on Windows 7 and I am having issues with the commandPort mel command. I have no idea if it is a Windows or Maya 2010 issue, but currently if I open a port with this command:

commandPort -n ":7092";

Maya says it's open but the program I used to "talk" to Maya on this port says it's not!

Also:

commandPort -n "localhost:7092";

doesn't open it either!

The strange thing is , if you execute BOTH commands one after another (at whatever order!) , the port opens and the other program finds it. This was working ok on other versions of Maya and on older Windows platforms. It bugged me for 2 hours today to find a workaround and obviously that's the only way I was able to "fix" it.