regarding: http://www.neuron.yale.edu/neuron/insta ... _unix.html
On ubuntu the readline library seems to be named in a way that nrn/.configure doesn't know about. (ubuntu is appending a version number to the .so files). So, if your make is failing and yelling about readline not compiling, it's probably because ./configure didn't actually find the library.
if you make a symlink to the library leaving off the version number, the ./configure should find the library and the compilation should be work.
> sudo ln -s /lib/libreadline.so.4 /lib/libreadline.so
> cd nrn
> ./configure --with-readline=/lib && make
Happy modeling.