diff --git a/AppKit/CPAlert.j b/AppKit/CPAlert.j
index 08c4fa030..1f6fe0c8b 100644
--- a/AppKit/CPAlert.j
+++ b/AppKit/CPAlert.j
@@ -137,7 +137,8 @@ var bottomHeight = 71;
     @delegate -(void)alertDidEnd:(CPAlert)theAlert returnCode:(int)returnCode;
     Called when the user dismisses the alert by clicking one of the buttons.
     @param theAlert the alert panel that the user dismissed
-    @param returnCode the index of the button that the user clicked (starting from 0,
+    @param returnCode the tag of the button that the user clicked. Unless a button's
+           tag has been changed, it is the button's index (starting from 0,
            representing the first button added to the alert which appears on the
            right, 1 representing the next button to the left and so on)
 */
diff --git a/AppKit/CPScrollView.j b/AppKit/CPScrollView.j
index 45f98d5f0..716d34550 100644
--- a/AppKit/CPScrollView.j
+++ b/AppKit/CPScrollView.j
@@ -207,7 +207,7 @@ var CPScrollerStyleGlobal                       = CPScrollerStyleOverlay,
         bounds.size.height -= [horizontalScrollerClass scrollerWidthInStyle:scrollerStyle];
 
     if (verticalScrollerClass)
-        bounds.size.width -= [verticalScrollerClass scrollerWidthForControlSize:scrollerStyle];
+        bounds.size.width -= [verticalScrollerClass scrollerWidthInStyle:scrollerStyle];
 
     return bounds.size;
 }
@@ -240,7 +240,7 @@ var CPScrollerStyleGlobal                       = CPScrollerStyleOverlay,
         frameSize.height += [horizontalScrollerClass scrollerWidthInStyle:scrollerStyle];
 
     if (verticalScrollerClass)
-        frameSize.width += [verticalScrollerClass scrollerWidthForControlSize:scrollerStyle];
+        frameSize.width += [verticalScrollerClass scrollerWidthInStyle:scrollerStyle];
 
     return frameSize;
 }
diff --git a/Foundation/CPDecimal.j b/Foundation/CPDecimal.j
index 54bb53353..98669882d 100644
--- a/Foundation/CPDecimal.j
+++ b/Foundation/CPDecimal.j
@@ -608,7 +608,7 @@ function CPDecimalAdd(result, leftOperand, rightOperand, roundingMode, longMode)
         // swap sign over over/underflow exception
         if (CPCalculationUnderflow == adderror)
             adderror = CPCalculationOverflow;
-        else if (CPCalculationUnderflow == adderror)
+        else if (CPCalculationOverflow == adderror)
             adderror = CPCalculationUnderflow;
     }
     else
diff --git a/Tests/AppKit/CPScrollViewTest.j b/Tests/AppKit/CPScrollViewTest.j
index be937a1c9..15ee3ec5c 100644
--- a/Tests/AppKit/CPScrollViewTest.j
+++ b/Tests/AppKit/CPScrollViewTest.j
@@ -379,5 +379,48 @@
     [self assertSize:expected.size equals:actual.size message:message]
 }
 
+- (void)testFrameSizeForContentSizeUsesScrollerStyleForBothScrollers
+{
+    var frameSize = [CPScrollView frameSizeForContentSize:CGSizeMake(100.0, 100.0)
+                                  horizontalScrollerClass:[_CPScrollViewTestScroller class]
+                                    verticalScrollerClass:[_CPScrollViewTestScroller class]
+                                               borderType:CPNoBorder
+                                              controlSize:CPRegularControlSize
+                                            scrollerStyle:CPScrollerStyleOverlay];
+
+    [self assertSize:CGSizeMake(105.0, 105.0) equals:frameSize message:@"both scroller widths come from scrollerWidthInStyle:"];
+}
+
+- (void)testContentSizeForFrameSizeUsesScrollerStyleForBothScrollers
+{
+    var contentSize = [CPScrollView contentSizeForFrameSize:CGSizeMake(100.0, 100.0)
+                                    horizontalScrollerClass:[_CPScrollViewTestScroller class]
+                                      verticalScrollerClass:[_CPScrollViewTestScroller class]
+                                                 borderType:CPNoBorder
+                                                controlSize:CPRegularControlSize
+                                              scrollerStyle:CPScrollerStyleOverlay];
+
+    [self assertSize:CGSizeMake(95.0, 95.0) equals:contentSize message:@"both scroller widths come from scrollerWidthInStyle:"];
+}
+
 @end
 
+
+/*!
+    A scroller whose widths differ by style, and whose control-size width differs
+    from both, so a size calculation that uses the wrong method is detectable
+    regardless of the theme.
+*/
+@implementation _CPScrollViewTestScroller : CPScroller
+
++ (float)scrollerWidthInStyle:(CPScrollerStyle)aStyle
+{
+    return aStyle === CPScrollerStyleOverlay ? 5.0 : 20.0;
+}
+
++ (float)scrollerWidthForControlSize:(CPControlSize)aControlSize
+{
+    return 99.0;
+}
+
+@end
diff --git a/Tests/Foundation/CPDecimalTest.j b/Tests/Foundation/CPDecimalTest.j
index 2c17741c7..3326d628d 100644
--- a/Tests/Foundation/CPDecimalTest.j
+++ b/Tests/Foundation/CPDecimalTest.j
@@ -468,6 +468,12 @@
     d1 = CPDecimalMakeWithString(@"1e127");
     d2 = CPDecimalMakeWithString(@"99999999999999999999999999999999999999e127");
     [self assert:CPDecimalAdd(d1, d1, d2, CPRoundPlain) equals:CPCalculationOverflow message:"CPDecimalAdd() Tao1: addition loss of precision"];
+
+    // Overflow of two negative operands is reported as underflow
+    d1 = CPDecimalMakeWithString(@"-1e127");
+    d2 = CPDecimalMakeWithString(@"-99999999999999999999999999999999999999e127");
+    [self assert:CPCalculationUnderflow equals:CPDecimalAdd(d1, d1, d2, CPRoundPlain) message:"CPDecimalAdd() Tao2: negative overflow is reported as underflow"];
+    [self assert:YES equals:d1._isNegative message:"CPDecimalAdd() Tao2: sign"];
 }
 
 - (void)testSubtract