manifest配置tabbar乱码问题

配置manifest的tabbar的时候，对图标配置，用\uexxx无效，以前的manifest配置的图标变成汉字了？如何解决？

{  
                                "tag" : "font",  
                                "id" : "cardIcon",  
                                "text" : "",  
                                "position" : {  
                                    "top" : "8px",  
                                    "left" : "40%",  
                                    "width" : "20%",  
                                    "height" : "22px"  
                                },  
                                "textStyles" : {  
                                    "fontSrc" : "_www/fonts/custom.ttf",  
                                    "align" : "center",  
                                    "size" : "22px"  
                                }  
                            },  
                            {  
                                "tag" : "font",  
                                "id" : "cardText",  
                                "text" : "打卡",  
                                "position" : {  
                                    "top" : "27px",  
                                    "left" : "40%",  
                                    "width" : "20%",  
                                    "height" : "24px"  
                                },  
                                "textStyles" : {  
                                    "align" : "center",  
                                    "size" : "10px"  
                                }  
                            },