Long waits still greeted Indiana Toll Road customers at the West Point toll plaza Monday, despite the start of I-Zoom electronic tolling that officials said would clear up the mess.

About noon, traffic was backed up from West Point to the toll plaza at mile marker 5 in Hammond. It was not clear if that was due to backups at the toll booths at West Point or the closure of a lane leading to the travel plaza.

In the morning, officials reported few problems, with about 85 percent of electronic toll lanes operating properly from the get-go, according to Indiana Toll Road spokesman Matt Pierce.

Antennae receiving transponder signals on the remainder of the lanes were to be recalibrated throughout the day to get 100 percent of electronic lanes operating, Pierce said. That may have caused some delays for motorists, but all Toll Road booths were staffed by collectors in order to aid customers, Pierce said.

I-PASS and E-ZPass transponders from 10 other states also now can be used on the Indiana Toll Road.

Having electronic tolling installed on the entire 157-mile length of the road was a key requirement of the state when it leased the road to a private operator for $3.8 billion last year. The start of electronic tolling on the road's 23 miles in Northwest Indiana is the first phase of that project.

"It's the first time in the 50-year history of the Toll Road that anyone is collecting electronic tolls," Pierce said Monday.

It has been a bumpy start to electronic tolling on the Indiana Toll Road. Illinois officials were outraged to learn that a 40 percent discount that will be extended to people with Indiana's I-Zoom transponders later this year initially would not be extended to people with I-PASS.

Months of negotiations led to a pledge two weeks ago by Gov. Mitch Daniels to pay whatever it takes so ITR Concession Co., the Toll Road's private operator, can offer the discount to all I-PASS and E-ZPass users.