problem in installing NS-2.26
 

Hi,
I want to install NS (Network Simulation)
I'm installing ns-2.26, all the packages were installed successfully, but when making ns-2.26 , in /tools/rng.cc below error apears:
"
error: `RNGTest' undeclared (first use this function)
"

but all things is Ok, I don't know why this error exists. rng.cc is one of its ns files.
plz help.

thanks in advance.