2.5 can't modify ui layout

Hey; i’m not sure if this is a bug or if i’ve accidently pressed a hot key of some kind that’s locked the ui layout.

While working on my scene (with all panels hidden) I attempted to drag the bottom panel header upwards (by the corner of the bar) however it did not split as expected.

As it is now i can resize the existing panels but am unable to split off new panels; does anyone have any ideas what i might have done? it’s rather a pain and afaik its not possible to reset the ui to factory defaults without having to import my scene into a new file (not a big problem but i’d rather know if i’ve pressed some lock key for future reference)

Get the latest Blender SVN >=360**
Click right mouse on the border and you get the old menu ( :wink: ) to split or combine windows.

Older version you have to click in the upper right corner … (works too in newer version)