[ns] segmentation fault

[karthik srinivas]

hello people,
i'm working with dsr code ...but i get a segmentation fault in the function common/packet.h : return(&bits_[off]) ....The segmentaion fault happens at the beginning of the simulation....i have made changes in the simulation script setting the protocol to DSR...can anyone help me regarding the changes i have to make....
thanx in advance,
karthik