Deep under the Science Center, the Harvard Yard Mail Center bustles with first-years checking party flyers and picking up letters home.

But behind the mailboxes is the front line in Harvard's battle to find and correctly pay former "casual workers."

"Casuals" are theoretically workers who works less than 17.5 hours per week or for no less than three months, and as a result receive no benefits and lower wages.

Over the summer, Harvard admitted that it had misclassified 400 to 500 employees who worked full-time as "casuals." In October, the University signed an agreement with the Harvard Union of Clerical and Technical Workers (HUCTW) to fix the situation and allow these full-time "casuals" better pay, benefits and union membership.

But that promise was easier said than fulfilled. A decentralized University structure and a nightmarish paper trail have made it difficult to identify who exactly needs to get full-time benefits.

In the Harvard Yard Mail Center, this has been more than a clerical problem. One casual employee, refusing to interview and apply for the full-time job he already filled, was let go.

Another casual worker, put on edge by the prospect that she would lose her full-time spot in the changeover, lost her cool and allegedly shoved a supervisor during an argument.

She was fired. Because she was not a union member at her firing, this employee says she lacks a way to fight Harvard's decision through an independent appeal.