huh? aah yeah just make sure youve actualy selected UVS not vertexes since you can only manipulate UV components in the uv editor. if your selectionb iis cvs then press contrl+ right mouse in the panel and convert it to uv selections.
And you allwasy needed to do that in mauuya have uvs selected.... anyway chak also that you have tsome manipulator on too!
uvs are a bit different form vertexes in thet one vertex can have many uvs so its not totaly usefuull to be able to select vertices in the uv editor.