Railway Board has decided to introduce Tatkal facility in Duranto Trains soon. Detail is given in the below link.
http://www.indianrailways.gov.in/railwayboard/uploads/directorate/traffic_comm/COMM-CIR-2K11/CC_67_2011.pdf
http://www.ecr.indianrailways.gov.in/uploads/files/1324036195724-Tatkal%20Scheme%20in%20Duronto%20Exp%20.pdf