NTT DoCoMo Inc. on Wednesday launched a trial run of its third-generation mobile phone service that promises to eventually allow users to watch video transmissions on their handsets.

The receivers DoCoMo has distributed for the trial so far do not allow for video transmissions. DoCoMo said Friday it is putting off distribution of video-capable models due to a software glitch.

Two receivers are currently being tested; one allows for faster i-mode service, while the other is a card that plugs into PCs for high-speed data transmissions.