Thanks for your fast reply. The package isn't there:
D:\Perl\Module>perl -e"use Math::GMP"
Can't locate Math/GMP.pm in @INC (@INC contains: D:/Perl/lib D:/Perl/s
at -e line 1.
BEGIN failed--compilation aborted at -e line 1.
I can open the package file Math-GMP-2.05.tar.gz with Winrar. While installing I had the problem, to get the ppd-file. For reasons I don't understand, the ppd-File isn't really accessible at the module download site. I had to install around 10 packages. The first method I used to get the ppd-files is to download it from http://theoryx5.uwinnipeg.ca/ppms/Module-Name.ppd. The second, if the ppd file wasn't there, is to take the very big package file package.xml and cut the needed part from that file and save it as ppd. I had to add an additional <Implementation>> - tag for getting this file to work.
My ppd-file for the module above is:
<SOFTPKG NAME="Math-GMP" VERSION="2,04,0,0">
<ABSTRACT>High speed arbitrary size integer math </ABSTRACT>
<OS NAME="MSWin32" />
<ARCHITECTURE NAME="MSWin32-x86-multi-thread-5.8" />
<CODEBASE HREF="Math-GMP-2.05.tar.gz" />
<PROVIDE NAME="Math::GMP" VERSION="2.04" />