Residential Lending Corp. agreed with Systems Automation Corp. to sublease 19,552 square feet at 4041 Powder Mill Road in Calverton, MD. The sublease runs through July of 2006. Although Systems Automation decided to vacate the space on the sixth floor, now being filled by Residential Lending, it didn't leave the building. It sub-leased 10,227 square feet on the fifth floor through 2006.