Adding a new column in WEBDB

Hi,

I was trying to add a new column into a form using WEBDB. I did the following steps:

1. Create a new date column using SQL plus
2. Select the existing form and click on Edit
3. Add a new item into the form using the same name as the column created in SQL plus
4. Click on Finish and Run the form
5. However, there are errors executing the form.
When i entered 04-DEC-00 for the date column, there is a validation error "Please enter alphanumeric value". I did not choose to validate the field in the form. I have to enter 041200 to get pass the field.
6. Anyway, I also did not enable to insert a new row successfully. :(

As I am new to webdb, so please advice me whether I am on the right track or not.
My questions:

1. What is the correct ways of adding a new column to an existing form in WEBDB?
2. When I have added the new column, it doesn't appear in the real form. Is it beacuse the run is not successful?
3. How do I link the new column to the column I have craeted in SQL plus?

Thanks a lot! :)