SafeSurf is a Parental Control/Child Safety framework and value-added service deployed by (StarHub) MaxOnline. Not only does it block adult content, it also prohibits access to legitimate sites including random IT-related portals and generic blogs which have been accidentally filtered by use of, I presume poor techniques, which Starhub does not disclose. Hence, not being exclusive to "porn".
Get your Customer ID and log in online to disable the service. If someone else is the subscriber then tell that person why this service is bad and needs termination as soon as possible. One would be better off using a Family-Safe extension/filter list for the browser; Opera and Firefox are known to have such solutions.