The Wisconsin Department of Revenue is working with service provider CGI-AMS Inc. to mend the flaws in the DOR's Integrated Tax System (ITS), said Laura Engan, deputy secretary at the DOR. CGI-AMS built the ITS more than three years ago.

CGI-AMS, which is a subsidiary of Montreal-based CGI Group Inc., this month started testing the system and fixing its performance problems, according to state officials.

A separate review of the system by CGI and state engineers is slated to be completed in April. CGI has agreed to fix any further problems found during the review.

"We're working with the vendor to fix the problem now," Engan said. "We'd like that to have happened earlier. We're just incredibly frustrated with the performance of the system and the outcomes we've seen."

She attributed the bulk of the problems to "design flaws" in the system as delivered by CGI-AMS in December 2002.