Focus of the Date field is lost on modifying Month or Weekday field, if the JFormattedTextField is having multiple Fields of Month/weekday associated with it.

manasa% java -version
java version "1.4.0-beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-beta-b58)
Java HotSpot(TM) Client VM (build 1.4.0-beta-b58, mixed mode)

To reproduce :

1. Compile & Run the attached program.
2. Move the cursor to 1st textField's Month field with complete month
   name, i.e., April
3. Press UP cursor key. You will see that focus moves to month field
   with 3 chars 'May'.
4. Move the cursor to 2nd textField's MMM field, i.e., 'Apr'.
5. Press DOWN cursor key. You will see that focus moves to month field
   with complete text 'March'.

This can be reproduced with Weekday also.