libsdl-mixer problem was that libsdl-mixer1.2 1:1.2.6-5+0m5+ogg+mp3 is wat is present in maemo extra while libsdl-mixer1.2 1:1.2.6-5+0m5 is needed which is in nokia system repo.
before updating via xterminal of app manager jst turn off maemo extra,extra-testing and extra-devel repo
maemo extra,extra-testing and extra-devel repo are all disabled in app manager ... infact extra testing and extra devel repo is not even subcribed to in catalogues ... problem still persists ...