trace/cmu-trace.o: In function `hdr_aomdv::access(Packet const*)':
cmu-trace.cc.text._ZN9hdr_aomdv6accessEPK6Packet[hdr_aomdv::access(Packet const*)]+0x7): undefined reference to `hdr_aomdv:ffset_'
trace/cmu-trace.o: In function `hdr_mdart::access(Packet const*)':
cmu-trace.cc.text._ZN9hdr_mdart6accessEPK6Packet[hdr_mdart::access(Packet const*)]+0x7): undefined reference to `hdr_mdart:ffset_'
collect2: ld returned 1 exit status
make: *** [ns] Error 1
Ns make failed!

This error made during ns 2.35 installation in ubuntu 11.04.
So please help me........

You need to install some essential packages using the following command:
sudo apt-get install tcl8.5-dev tk8.5-dev sudo apt-get install build-essential autoconf automake sudo apt-get install perl xgraph libxt-dev libx11-dev libxmu-dev

Then, try to install ns 2.35 again.

Welcome to LQ.

sudo apt-get install g++-4.4

Please start from scratch with a new unpacked ns-allinone-2.35.tar.gz :
cd ns-allinone-2.35/ && export CC=gcc-4.4 CXX=g++-4.4 && ./install

( Or 'make clean' and delete 'Makefile' in tcl8*/unix/, tk8*/unix/,
otcl*/, tclcl*/, ns-2.35/ before the above command.)

EDIT : Ref. post # 2 : Please do not install any tcl8.5-dev tk8.5-dev !

.