diff --git a/src/pkg/fmt/doc.go b/src/pkg/fmt/doc.go
index c993e57a40..6713f0a16e 100644
--- a/src/pkg/fmt/doc.go
+++ b/src/pkg/fmt/doc.go
@@ -89,10 +89,14 @@
 	If an operand implements interface Formatter, that interface
 	can be used for fine control of formatting.
 
-	If an operand implements method String() string that method
+	Next, if an operand implements the error interface, the Error method
 	will be used to convert the object to a string, which will then
-	be formatted as required by the verb (if any). To avoid
-	recursion in cases such as
+	be formatted as required by the verb (if any).
+
+	Finally, if an operand implements method String() string that method
+	will be used to convert the object to a string, which will then
+	be formatted as required by the verb (if any).
+	To avoid recursion in cases such as
 		type X int
 		func (x X) String() string { return Sprintf("%d", x) }
 	cast the value before recurring:
diff --git a/src/pkg/fmt/print.go b/src/pkg/fmt/print.go
index f80ce7c927..5e0237f454 100644
--- a/src/pkg/fmt/print.go
+++ b/src/pkg/fmt/print.go
@@ -630,12 +630,23 @@ func (p *pp) handleMethods(verb rune, plus, goSyntax bool, depth int) (wasString
 			return
 		}
 	} else {
-		// Is it a Stringer?
-		if stringer, ok := p.field.(Stringer); ok {
+		// Is it an error or Stringer?
+		// The duplication in the bodies is necessary:
+		// setting wasString and handled and deferring catchPanic
+		// must happen before calling the method.
+		switch v := p.field.(type) {
+		case os.Error:
 			wasString = false
 			handled = true
 			defer p.catchPanic(p.field, verb)
-			p.printField(stringer.String(), verb, plus, false, depth)
+			p.printField(v.String(), verb, plus, false, depth)
+			return
+
+		case Stringer:
+			wasString = false
+			handled = true
+			defer p.catchPanic(p.field, verb)
+			p.printField(v.String(), verb, plus, false, depth)
 			return
 		}
 	}