[Flow] Using Chinese characters as Identity for Object Route Parts

[Rocky]

Hi,

The system I am developing uses Chinese Only. I tried to configure the router as below:
 -                                                                                                                  
    name: 'DashboardSchool'                                                                                          
    uriPattern: 'dashboard/school/{school}'                                                                          
     defaults:                                                                                                        
      '@package': 'Hwwcn.Sponsor'                                                                                    
      '@controller': 'Dashboard'                                                                                     
      '@action': 'school'                                                                                            
      '@format': 'html'                                                                                              
    routeParts:                                                                                                      
      school:                                                                                                        
        objectType: '\Hwwcn\Sponsor\Domain\Model\School' 

But in the address bar I got http://mydomain.com/dashboard/school/-2 instead of http://mydomain.com/dashboard/school/测试学校. Any idea please?