Today works with Centos 5.2
# rpm -qa|grep qt
qt-3.3.6-23.el5
You need upgrade centos 5.2 all.
In this test i use:
# rpm -qa|grep kernel
kernel-headers-2.6.18-92.1.22.el5
kernel-xen-2.6.18-92.1.22.el5
kernel-devel-2.6.18-92.1.22.el5
]# rpm -qa|grep gdm
gdm-2.16.0-46.el5.centos
# rpm -qa|grep vnc
gtk-vnc-0.3.2-3.el5
vnc-4.1.2-9.el5
vnc-server-4.1.2-9.el5
gtk-vnc-python-0.3.2-3.el5
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