Cocoa – Why would NSWindow with NSTableView not resize

Here is my IB setup:

http://img145.imageshack.us/img145/5929/picture1gxr.png

When both NSScrollView and NSTableView are set to autoresize and autofill (all the arrows in the Autosizing section are checked) my window does not resize. Actually it resizes, but by a pixel, as if it remembers that it is not supposed to resize after I start dragging the corner. If I uncheck the autofill arrows (disabling NSViewWidthSizable and NSViewHeightSizable) on the NSScrollView, the window resizes fine, but of course, the scroll view does not resize with it.

The weird thing is that in the situation where the window is "rigid" if I resize one of the NSTableView's columns beyond the view (thus causing a horizontal scroll bar to appear), I can resize the window but only until it reaches the size big enough to accommodate all the columns and then becomes rigid again.