Comment 19 for bug 855171

For anyone hit by this bug and unable to get a working network to fix it, I found another copy of libnss3.so on my system from the firefox package at /usr/lib/firefox-7.0/libnss3.so. Copying it to /usr/lib allowed network-manager to start, so then I could download and reinstall the libnss3 package as described above. Worth a try if you're stuck.