Script to copy values to work items

                                                                        
I need a script to copy values as follows.                              
                                                                        
I have a Business Need work item and 3 attributes as Planned Start      
Date, SLA and Planned End Date                                          
                                                                        
Now I need to copy the above 3 values to the TASK work item linked to   
the Business Need. The TASK work item will also have the above 3 fields.
                                                                        
Request your help for a DOJO script URGENTLY.                                
                                             
Regards
Niranjan V