Dynamic CCK fields population

How can I create two CCK fields where the latter has values based on the first selection?

In my case I have a few programs which can be selected and then projects that are related to programs. I need to have two separate fields for them.

Example:

Programs:

• Program1

• Program2

Projects:

• Project1 (related to Program1)

• Project2 (related to Program2)

• Project3 (related to Program2)

If program "Program1" is selected, then the user should only be 开发者_JAVA百科able to select "Project1" and in case of "Program2" is selected, the options should be "Project2" or "Project3".

I'm using Drupal 6.20 and I've already tried using Conditional Fields and Computed Fields modules, but they don't really solve my problem.

Any help is much appreciated!

I found a suitable module for my needs. Hierarchical Select solved my problem.