JACKSON, Miss. (AP) — A computer glitch in new software at the Public Employees Retirement System is causing a large backlog in processing pension applications for some newly retired former state employees. "This new system replaces our former system, which was more than 16 years old and, as such, was operating at an exceedingly slow pace," said PERS Executive Director Pat Robertson told The Clarion-Ledger (http://on.thec-l.com/1M0IUMb). Robertson said state employees who retired in June won't receive their first benefits check until at least Jan.