diff -r 08d2b9deb710 -r 1af366d10d32 structs.go
--- a/structs.go	Mon Jan 02 10:01:41 2012 -0700
+++ b/structs.go	Mon Jan 02 13:18:48 2012 -0700
@@ -271,6 +271,9 @@
 }
 
 func (u *Generic) String() string {
+	if u == nil {
+		return "nil"
+	}
 	var sub string
 	if u.Any != nil {
 		sub = u.Any.String()