OpenSUSE Network :: WebYast Updates Module - Mesages Say Wait ?

I recently installed OpenSuSE 11.4 including WebYast base system with all available modules. Status shows everything works fine. But the update module has some problems. It displays 21 updates, three of them security and 18 important. By clicking on any of the install buttons the mesages say please wait and then updating while the update time depends on the size of the file. It finishes and goes back to the list of updates without any error message. But after that never shows up any changes or messages that the update has actually installed. Since about ten days the list always remains the same.