Installation error message

[fang@asl.dl.nec.com (Kuoling Fang)]

Hi, 

I'm trying to install a copy of release 2.1b3. I run ./install script to
install it. I got the following error output. Could you take a look at it
and kindly tell me how to fix this. Thank you in advance!

============================================================================

[138]youn@ranger% make

g++  -o ns \
        tclAppInit.o  random.o rng.o ranvar.o misc.o timer-handler.o  scheduler.
o object.o  packet.o ip.o route.o connector.o ttl.o  trace.o trace-ip.o  classif
  ...
_tcl.o  win32.o -R../TclCL -L../TclCL -ltclcl -R../otcl -L../otcl -lotcl -R../tk
box/lib -L../tkbox/lib -ltk8.0 -R../tclbox/lib -L../tclbox/lib -ltcl8.0   -lXext
 -lX11  -lsocket -lnsl -ldl -ldl  -lm -ldl
Undefined                       first referenced
 symbol                             in file
handle__19SnoopPersistHandlerP5Event snoop.o
ld: fatal: Symbol referencing errors. No output written to ns
*** Error code 1
make: Fatal error: Command failed for target `ns'

==========================================================================

K. Fang