I used to have that kind of issue as well, how i solved it:

1. go to settings
2. More...
3. Mobile networks
4. Access Point Names
5. Tap "Maxis 3G" or any operator name (tap on the name, not the round check box on the right)
6. look for "Proxy"
7. remove the proxy ip

Then you are done.

actually i learnt from other forumer here, forgot who already. long time ago, when the phone was still new in the market...