co-incidence, i was just right now configuring directed retry on a ZTE BSS to relieve the congestion. What version of ZTE BSS are you using? If the version is 2.95 or later then you can activate it through the radio resource management interface. Right click the cell parameters and go to Service Process Additional Params and check the parameter drind(directed retry indication). From the performance i can see that it is working although SDCCH handover is disabled.