A recent update updated lot of packages on Centos 5. Then next update 
try to replace x86_64 libs by i686 libs with lot of unresolved dependencies.

yum check-update gives:

> Obsoleting Packages
> tdelibs.i686                           3.5.13-9.el6.opt       trinity-3.5.13-el5
>     trinity-kdelibs.x86_64             3.5.13-8.el5.opt       installed
> tdelibs-devel.i686                     3.5.13-9.el6.opt       trinity-3.5.13-el5
>     trinity-kdelibs-devel.x86_64       3.5.13-8.el5.opt       installed

Fortunately, installing tdelibs.x86_64 solves the problem.
-- 
Philippe BOURDEU d'AGUERRE
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