hi. i've installed yum and yumex and i have it configured just like the tutorials say but i'm having trouble installing som of the packages. i have updated almost all the packages available but some of them are giving me signature check error. i have installed mplayer and vlc and they are working fine but i would like to install another player for music like amarok. the problem is that i cant get the mp3 codecs for any music player. amarok is based on xine and i need to get some packages like xine-lib or so but yumex tells me it needs some package like libavcodec. do you know anything about these errors

thx