Steps to Reproduce:

1.Create a new person search select advance field (oppo_agent) and add it to the opportunity web picker screen.
2. Find an opportunity that's not associated with a Person & click "Change"
3. Click on New Person and enter in person details select Save & Continue


Actual result (please include text of any error message):

The person is added to the oppo_agent web picker screen instead of the oppo_primarypersonid field

Expected result:

The person should be added to the oppo_primarypersonid field

Workaround:

Add the oppo_agent field to a screen other than opportunity web picker

Solution:
Fixed in 7.1k and 7.2c