2.53?
2.49?
d2
2.53?
2.49?
d2
A simple search for clipping border in the wiki brings up the result
http://wiki.blender.org/index.php/Doc:Manual/3D_interaction/Navigating/3D_View#View_Clipping_Border
2.49 - in camera view (numpad 0), press shift B to select a border - to remove, toggle the “border” button in the Render Tab or the scene buttons (F10)
2.53 - Shift B will allow you to choose the border - to remove, uncheck the Border toggle in the “Dimension tab” of the render buttons
Or just do a new border with SHIFT+B which enconpasses the full render region.