From the website: "NSP allows you to identify word n-grams that appear in large corpora using standard tests of association such as Fisher's exact test, the log likelihood ratio, Pearson's chi-squared test, the Dice Coefficient, etc. NSP has been designed to allow a user to add their own tests with minimal effort." Version v1.01 has been released June 23, 2006. It's written in Perl. Version 0.05 was tested in Gentoo: http://nntp.x.perl.org/group/perl.cpan.testers/175247 I installed NSP 0.91 through manual compiling, couldn't write an ebuild. So far, so good.
No progress here for over 1 year; closing WONTFIX. Feel free to reopen with an ebuild.