[Yum] Yum Dependency Resolution algorithm clarification

[Pauwel Coppieters]

Hello,
        
        I have some trouble understanding how dependency resolution
        works in
        yum (2.6.1).
        
        There is on my system an old version of transcode I would like
        to
        update. A newer version from RPMForge has a dependency on
        libpostproc.so.0.0.1
        
        >
        > $ yum deplist transcode
        > Finding dependencies: 
        > Setting up repositories
        >
        rpmforge                                                             
        >
        updates-released                                                     
        >
        base                                                                 
        >
        extras                                                               
        > Reading repository metadata in from local files
        > package: transcode.i386 1.0.2-7.fc4.rf
        >   dependency: libpostproc.so.0.0.1
        >    Unsatisfied dependency
        > 
        
        There is no package that provides libpostproc.so.0.0.1. However
        a
        local package is installed that provides libpostproc.so.0.0.1
        
        > 
        > $ yum whatprovides libpostproc.so.0.0.1
        > Searching Packages: 
        > Setting up repositories
        >
        rpmforge                                                             
        >
        updates-released                                                     
        >
        base                                                                 
        >
        extras                                                               
        > Reading repository metadata in from local files
        > Importing additional filelist information
        > 
        > 
        > libpostproc.i386               1.0-0.14.pre6a.1.fc3.f
        installed             
        > Matched from:
        > /usr/lib/libpostproc.so.0.0.1
        > 
        
        Eventually, yum fails to update transcode (see below). Is this
        intended behaviour, or should this work. If so, any directions
        as
        where to change in the source ?
        
        Greetings
        
        Pauwel Coppieters
        
        
        > 
        > # yum  update transcode
        > Setting up Update Process
        > Setting up repositories
        >
        rpmforge                                                           
        >
        updates-released                                                    
        >
        base                                                                 
        >
        extras                                                               
        > Reading repository metadata in from local files
        > Resolving Dependencies
        > --> Populating transaction set with selected packages. Please
        wait.
        > ---> Package transcode.i386 0:1.0.2-7.fc4.rf set to be updated
        > --> Running transaction check
        > --> Processing Dependency: libmpeg2convert.so.0 for package:
        transcode
        > --> Processing Dependency: libpostproc.so.0.0.1 for package:
        transcode
        > --> Processing Dependency: libmpeg2.so.0 for package:
        transcode
        > --> Restarting Dependency Resolution with new changes.
        > --> Populating transaction set with selected packages. Please
        wait.
        > ---> Package mpeg2dec.i386 0:0.4.0-8b.fc4.rf set to be updated
        > --> Running transaction check
        > --> Processing Dependency: libpostproc.so.0.0.1 for package:
        transcode
        > --> Finished Dependency Resolution
        > Error: Missing Dependency: libpostproc.so.0.0.1 is needed by
        package
        transcode
        >