when a program is compiled with libwrap support, it is so that network access to the program can be controlled using TCP Wrappers if one wishes... in other words, with the
hosts.allow and
hosts.deny files, etc... so in answer to your question: libwrap allows xinetd to use TCP Wrappers...
here's an informative link:
http://www.redhat.com/docs/manuals/e...pwrappers.html