Text display is incomplete

[jhunters]

Did any one has this problem? the text display in class diagram with chinese will show incomplete.
classDiagram
Animal <|-- 鸭子
Animal <|-- Fish
Animal <|-- Zebra
Animal : +int age
Animal : +String gender
Animal: +isMammal()
Animal: +mate()
class 鸭子 {
+String beakColor
+swim()
+quack()
}
class Fish{
-int sizeInFeet
-canEat()
}
class Zebra{
+bool is_wild
+run()
}