National University has one. I don't know about four week classes though... http://www.nu.edu/Academics/Schools/COLS/ArtHum/Degrees/710-504.html
California State University Dominguez Hills' www.csudh.edu Master of Arts in Humanities External Degree Program offers the degree with an emphasis in Literature.
If DETC is okay with you, Harrison Middleton University (formerly known as the College for the Humanities and Sciences www.chumsci.edu) offers a Master of Arts in Imaginative Literature based on the Great Books of the Western World.
If a summer-only MA in English would work for you, such programs are available at the University of California Irvine www.uci.edu , the University of Maine www.umaine.edu , and Indiana University of Pennsylvania www.iup.edu .
Foreign (thesis-only) master's degrees in English are available at the University of Melbourne www.unimelb.edu.au , the University of New England www.une.edu.au , and the University of Teesside www.tees.ac.uk .