Uninstalling glib

[Oodini <svdbg free fr>]

Hello,

I tried to run the gtk configure, but it says me that I need to install ATK.
Then I try to install ATK, but I get the following message:

checking for GLIB - version >= 2.0.0...
*** 'pkg-config --modversion glib-2.0' returned 2.4.2, but GLIB (2.0.6)
*** was found! If pkg-config was correct, then it is best
*** to remove the old version of GLib. You may also be able to fix the error
*** by modifying your LD_LIBRARY_PATH enviroment variable, or by editing
*** /etc/ld.so.conf. Make sure you have run ldconfig if that is
*** required on your system.
*** If pkg-config was wrong, set the environment variable PKG_CONFIG_PATH
*** to point to the correct configuration files
no
configure: error:
*** GLIB 2.0.0 or better is required. The latest version of
*** GLIB is always available from ftp://ftp.gtk.org/. If GLIB is installed
*** but not in the same location as pkg-config add the location of the file
*** glib-2.0.pc to the environment variable PKG_CONFIG_PATH.

So how to completely uninstall the old glib, so that I can install again 
the new glib, and not to get the previous message when I try to install 
ATK ? Thanks.