Digital Telecommunications Philippines (Digitel) has denied accusations from its customers that it is deliberately blocking them from using retail pre-paid internet cards to access dial-up services from rival ISPs. The telco has refuted the claims, noting that such practice is against the law, and says the problems are the result of congestion issues on its network. Nevertheless, concerns have been voiced over the quickness with which Digital is advising customers to use its own pre-paid dial-up ‘Gas’ card instead. The dial-up cards being blocked by Digital include ISP Bonanza, Blast, SurfMax, Evolve of the Pacific Internet, Infocom and GO of Eastern Telecoms. The rival ISPs are believed to be preparing to file a complaint with the National Telecommunications Commission.