hello all, plaese tell me how can i pass a hash table to the javascript from a perl function as an arguments?

i'm trying as below...in perl function hash table sent as an argument, in javascript it is receiving as below....but its not working,,,,
Code:
 HashRowUnit=argv[1];  
  
    alert('size of hash table ' +HashRowUnit.length); 
  
  
for (var k in HashRowUnit) {   
if (HashRowUnit.hasOwnProperty(k)) {  
alert('key is: ' + k + ', value is: ' + HashRowUnit[k]);} }