Populate Drop down values to Adobe forms

Hello,

I am in the process of developing the HCM forms for PCR's. This is using old technology. How can I pass values to the Adobe forms based on certain condition selected in previous screen. For eg. Based on Position selected, I should have a certain value in Drop down pre-selected on the next screen and when the user does a drop down a list of the values should be listed. Where should do the coding for the subsequent drop down values?

Appropriate points rewarded.

Prasad