error in ns installation

*LOADS* ~ infinitely many warnings like this

./common/packet.h:255: warning: deprecated conversion from string constant to ‘char*’
./common/packet.h:258: warning: deprecated conversion from string constant to ‘char*’
./common/packet.h:261: warning: deprecated conversion from string constant to ‘char*’
./common/packet.h:264: warning: deprecated conversion from string constant to ‘char*’
./common/packet.h:266: warning: deprecated conversion from string constant to ‘char*’

and finally :
queue/red.cc: In member function ‘virtual void REDQueue::trace(TracedVar*)’:
queue/red.cc:874: error: invalid conversion from ‘const char*’ to ‘char*’
queue/red.cc:875: error: invalid conversion from ‘const char*’ to ‘char*’
queue/red.cc:876: error: invalid conversion from ‘const char*’ to ‘char*’
queue/red.cc:877: error: invalid conversion from ‘const char*’ to ‘char*’
make: *** [queue/red.o] Error 1
Ns make failed!