InfoPath Dev

I have a 2 cascading dropdown list boxes where data were populated by webservices. When the form first filled in by the user the drop down behave correctly. But when the user click on the existing form the second dropdown list box
did not populated the data correctly - The values should have been the Field_Description instead of Field_ID. Each of my dropdown box defined the Field_ID as Value and Field_Description as DisplayName. How do i rectify the problem?
Thank you in advance.

No one has any idea? Experts?

DD1 = your first drop-down / DD2 = your second drop-down

What you have going on is that the DD1 values query on load. The DD2 values query when DD1 changes (since the list is filtered). The value for DD1 does not change on load, and thus the DD2 values are not queried.

The fix is to add a loading rule which queries the DD2 values if the selection in DD1 is not blank.

Can you be more specific on "loading rule"? Is it a specific rule on Load.  I had a rule already on DD1 which contains:
Condition: DD1 is not blank
Action1: Clear existing content of DD2
Action2: set the value of DD1
Action3: Query using a data connection:GetValueForDD2 using DD1 value set in Action2.

I found this post: http://www.bizsupportonline.net/infopath2007/infopath-basics-how-to-populate-form-when-opened-loaded.htm 
so i added some rules to to Open and Save and it worked. I am not convinced as why i need to do that since i have rules in those dropdown list boxes already.

Well, here is the thing with rules on fields -- they only fire when the field changes. When your user opens a filled out form, none of the rules you have set on your first drop down would run unless he or she changes the value that is selected. That's why you need to run your query again when opening existing XML. Remember, form templates only store data in the main data source -- anything from a secondary data source has to be queried for.

I am facing same problem.Can you please give any example how do i implement on  load to fill dropdownlist on edit mode.