I am also interested in this strange lacking of good time administration of the basic Perl.(it seems that it allways backed on C code to solve this problem)

Define good :-)

For many uses the support for dates and time in the core language is all you need. If you need more there are many other modules that offer support. Personally I'm against adding things to the core language that are better supported by external modules. Once you move something into the core language you tie updates and bug fixes to new versions of perl.

At the Perl Date Time Project? (it recently looks a bit forgotten)

Not sure where you get this impression. The DateTime modules have been hitting CPAN on an impressively regular basis. And jolly good they are too.