Originally Posted by sounreal
This is what I did. And I did not port my number just to avoid problems.
Create a new APN with the following values:
APN Name: Straight Talk
MMS Proxy: 188.8.131.52
MMS Port: 80
Delete the current APN from your phone. Reboot your phone.
After I signed up that's what the website said to do.
Recommendations on XDA are to leave Proxy and Port blank. It works for me. I believe the proxy merely allows them to filter your traffic, preventing the use of some apps or services.