How to set mouse wheel to zoom in keymaps?

In the latest builds of blender (53413), the default behavior of the mouse wheel has changed drastically in OSX. It no longer zooms, but rotates the scene in the horizontal axis. Also it makes adding multiple edge-loops (CNTL+R) and setting the size of proportional editing impossible. (afaik)

I just want to set the mouse wheel back to zoom in key maps. Is this the right way to go? Is it possible? Anyone know how?

Sorry. It was a temporary change of mouse wheel/trackpad behavior that has now been fixed in SVN.