EDIT: I assume you're using a normal i386 compatible processor.
How did you end up in having ncurses from a new system?
Anyway, here is what you asked for, you can take it from: http://launchpadlibrarian.net/123667354/libc6_2.16-0ubuntu6_i386.deb (launchpad) By extracting the package (for example on Windows using 7zip) and taking libc.so.6 out of it. (in lib/i386-linux-gnu/) For amd64 you just need to adapt it. However do NOT install this package by overwriting! Just use libc.so.6 if that was the workaround, else your server is most likely screwed up. Even though it's from another distribution this normally works.
In case you are on Linux and you don't want to reboot or whatever, here is a way to unpack it on Linux.
# mkdir libc # cd libc # ar x ../libc6_2.16-0ubuntu6_i386.deb # tar xzf data.tar.gz
now you should have a directory with all .so files in the libc6 package.
Oh, and be careful, libc.so.6 is actually a link to libc-2.16.so here so you want to copy libc-2.16.so and not libc.so.6