Clicking 'New package' radio button clears the field

Description of problem:
When creating a new data object, the radio button for selecting/typing a new package clears the package typed in. This behaviour is unexpected and not really correct.

Version-Release number of selected component (if applicable):
BPMS 6.0 ER4

Steps to Reproduce:
1. Open Data Modeler, start creating a new data object.
2. Select 'New package' and fill in some package name.
3. Click 'New package' again.

Actual results:
The package is cleared.

Expected results:
Nothing changed, the package filled in in step 2 is still there.