To display Between Months in the Report

[Cognos_Problems]

Hi All,

I have a requirement like this :

In my report i have two value prompts:
1)Fromdate :which has month as source  dataitem in the format Jan-10 , the values of this prompt are from Jan-10 to Dec-10
2) Todate : which has month as source  dataitem in the format Jan-10 , the values of this prompt are from Jan-10 to Dec-10

when i run the report my report should filter the data based on these two pronpts and should dispaly the data , I have Month column also included in the list report.

so If select Jan-10 in From date value prompt and Apr-10 in To date value prompt my report show all the data in between these two dates.

I have tried like this :

1)between((to_char ('Parameter1'),'MON-YY') and (to_char ('Parameter2'),'MON-YY')).

2)between((cast_date ('Parameter1'),'DD-MON-YYYY') and (cast_date ('Parameter2'),'DD-MON-YYYY')).

Can any one give me the correct expression plz..........