[FC3] glibc problem with yum

["Danny Terweij - Net Tuning | Net" <d terweij nettuning net>]

yum info glibc :

[...cut...]
Name : glibc
Arch : i686
Version: 2.3.6
Release: 0.fc3.1
Size : 12 M
Repo : installed
Summary: The GNU libc libraries.
[...cut...]
Available Packages
Name : glibc
Arch : i386
Version: 2.3.6
Release: 0.fc3.1
Size : 4.2 M
Repo : legacy-updates
Summary: The GNU libc libraries.

Duplicate packages? Why so much in size different?  How to solve my problem
that an application cant find a proper glibc.

Danny.