check bottom of this post for update

just bought 256x256 head texture,
so i deactivated my old 128x128 texture and when i activate my new 256x256, this message comes up:




and when i go to textures, i can see my head texture is deactivated, in same time i can see it is activated in "Activated" tab
some weird bug?

UPDATE:

i was uploading it to the wrong slot :/
right slot is few scrolls down.

but now i have different problem,
when i upload 256x256 .PNG texture to the "256x256 Head Texture" slot, and then i click on image and then i click on "View Image Info", it say dimensions are 128x128 and file type is .JPG
so, why does automatically downscales and changes file type?