Step1:
Android 2.3 and lower
Settings > Wireless & Networks > Mobile Networks > Access Point Names > New APN setting (or a plus sign)
Android 4.0 and higher
Settings > More... > Mobile Networks > Access Point Names > New APN setting (or a plus sign) *Some models might have a slightly different path
Step 2:
You will need to input the following info:
Name: Public
APN: sp.mb.com
Proxy: Leave blank
Port: Leave blank
Username: Leave blank
Password: Leave blank
Server: Leave blank
MMSC: http://aliasredirect.net/proxy/mb/mmsc
MMSC proxy: 74.49.0.18
MMS port: 80
MCC: 302
MNC: 220
Authentication type: Leave blank
APN type: Leave blank
Step 3:
Select Save/Done. Select Public Mobile to connect to the Public Mobile network. Your data should work normally now.