Below are links for this excellent corporate PENTEST tool.  Architecturally, the new version uses a subroutine approach for specialized analysis to ensure the main engine stays efficient. 

Star PENTEST Tool — Nmap 5.50 Released
http://isc.sans.edu/diary.html?storyid=10330

Star Nmap 5.50 Documentation
http://nmap.org/nsedoc/

Star Nmap 5.50 Change Log
http://nmap.org/changelog.html

Star Nmap 5.50 Download (about 19MB)
http://nmap.org/download.html

QUOTE: A new update of one of the handlers’ favourite tool was released today.  A primary focus of this release is the Nmap Scripting Engine, which has allowed Nmap to expand up the protocol stack and take network discovery to the next level.  Nmap can now query all sorts of application protocols, including web servers, databases, DNS servers, FTP, and now even Gopher servers!  Remember those?  These capabilities are in self-contained libraries and scripts to avoid bloating Nmap’s core engine.