try this q/a
http://stackoverflow.com/questions/1049833/multi-valued-hashtable-in-java
I too encountered same issue earlier.
As per your screenshot, letter "t" in "Hashtable" is used in upper case. can you modify it and check again.
Modified line:
Hashtable<String,Hashtable<String,String>>table= new Hashtable<String,Hashtable<String,String>>();
Anyways, even after modifying it, check with Ashish team for exact rootcause of this issue.
Thanks SK.. It worked...
[i:2mlf1e6q]Hashtable<String,Hashtable<String,String>> table = new Hashtable<String,Hashtable<String,String>>();
table.put("name",[b:2mlf1e6q] table1[/b:2mlf1e6q]);
table.put("zip", [b:2mlf1e6q]table2[/b:2mlf1e6q]);[/i:2mlf1e6q]
Also had to remove "" from table1 and table2