The trial, involving the registering of 10,000 volunteers to record and test biometric ID data, was originally due to launch in February but did not begin until last week and as a result the length of the project has been cut from six months to three months.
The UK Passport Service is running the project with its technology partner Atos Origin, which inherited the deal through its acquisition of SchlumbergerSema.
But at a Home Affairs select committee this week, Blunkett and the UKPS admitted that the system that Atos Origin initially delivered was hit by problems and had to be sent back to the firm after a few weeks.
Problems with the hardware, software and the capture and recognition of data have forced adjustments to the resolution and focus of the facial-recognition camera, along with modifications to the background used for iris scanning.
A spokesman for the Home Office told silicon.com that the problems have now been rectified and that the trial is running smoothly.
"We have to make sure it is correctly configured before launching it. It's essential we get the first installation right before it is rolled out across the country. We'll learn our lessons from this," he said. "There were issues of failure in the equipment but those have been rectified and the technical problems have been ironed out."
No-one at Atos Origin was available for comment and NEC, which is providing the fingerprint-recognition technology for the project, said the Home Office will not allow it to comment.