diff --git a/browser/app/profile/firefox.js b/browser/app/profile/firefox.js
index 47d33537271..b0950354b1d 100644
--- a/browser/app/profile/firefox.js
+++ b/browser/app/profile/firefox.js
@@ -321,18 +321,29 @@ pref("intl.menuitems.insertseparatorbeforeaccesskeys","chrome://global/locale/in
 // On OS X, if the wheel has one axis only, shift+wheel comes through as a
 // horizontal scroll event. Thus, we can't assign anything other than normal
 // scrolling to shift+wheel.
-pref("mousewheel.withmetakey.action",3);
+pref("mousewheel.withshiftkey.action",0);
+pref("mousewheel.withshiftkey.sysnumlines",true);
+pref("mousewheel.withshiftkey.numlines",1);
+pref("mousewheel.withaltkey.action",2);
+pref("mousewheel.withaltkey.sysnumlines",false);
+pref("mousewheel.withaltkey.numlines",1);
+pref("mousewheel.withmetakey.action",0);
 pref("mousewheel.withmetakey.sysnumlines",false);
-pref("mousewheel.withcontrolkey.action",2);
-pref("mousewheel.withcontrolkey.sysnumlines",false);
+pref("mousewheel.withmetakey.numlines",1);
 #else
-pref("mousewheel.withcontrolkey.action",3);
-pref("mousewheel.withcontrolkey.sysnumlines",false);
 pref("mousewheel.withshiftkey.action",2);
 pref("mousewheel.withshiftkey.sysnumlines",false);
-#endif
+pref("mousewheel.withshiftkey.numlines",1);
 pref("mousewheel.withaltkey.action",0);
 pref("mousewheel.withaltkey.sysnumlines",false);
+pref("mousewheel.withaltkey.numlines",1);
+pref("mousewheel.withmetakey.action",0);
+pref("mousewheel.withmetakey.sysnumlines",true);
+pref("mousewheel.withmetakey.numlines",1);
+#endif
+pref("mousewheel.withcontrolkey.action",3);
+pref("mousewheel.withcontrolkey.sysnumlines",false);
+pref("mousewheel.withcontrolkey.numlines",1);
 
 pref("profile.allow_automigration", false);   // setting to false bypasses automigration in the profile code
 
diff --git a/browser/locales/en-US/chrome/help/mouse_shortcuts.xhtml b/browser/locales/en-US/chrome/help/mouse_shortcuts.xhtml
index 4f52e4d5250..43b7721a8a5 100644
--- a/browser/locales/en-US/chrome/help/mouse_shortcuts.xhtml
+++ b/browser/locales/en-US/chrome/help/mouse_shortcuts.xhtml
@@ -34,7 +34,7 @@ Contributors:
     <tr>
       <td>Back</td>
       <td>
-        <span class="mac">&ctrlKey;+Scroll Down</span>
+        <span class="mac">&altKey;+Scroll Down</span>
         <span class="noMac">&shiftKey;+Scroll Down</span>
       </td>
     </tr>
@@ -44,18 +44,18 @@ Contributors:
     </tr>
     <tr>
       <td>Decrease Text Size</td>
-      <td>&accelKey;+Scroll up</td>
+      <td>&ctrlKey;+Scroll up</td>
     </tr>
     <tr>
       <td>Forward</td>
       <td>
-        <span class="mac">&ctrlKey;+Scroll up</span>
+        <span class="mac">&altKey;+Scroll up</span>
         <span class="noMac">&shiftKey;+Scroll up</span>
       </td>
     </tr>
     <tr>
       <td>Increase Text Size</td>
-      <td>&accelKey;+Scroll down</td>
+      <td>&ctrlKey;+Scroll down</td>
     </tr>
     <tr>
       <td>New Tab</td>
@@ -88,7 +88,10 @@ Contributors:
     </tr>
     <tr>
       <td>Scroll line by line</td>
-      <td>&altKey;+Scroll</td>
+      <td>
+        <span class="mac">&accelKey;+Scroll</span>
+        <span class="noMac">&altKey;+Scroll</span>
+      </td>
     </tr>
   </tbody>
 </table>