Roll Over effect in ScrollBar in Combobox is different than native Win XP.

Steps to reproduce:
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1) Open SwingSet2 on Win Xp and change the LAF to Windows.
2) Go to ComboBox Dmeo.
3) Click on first combo and take the scroll bar thumb to the top. Observe that the scroll bar thumb is showing rollover effect .
4) Now Open Wordpad on Windows. And click on the Font Combo and repeat the step 3. There will be no Roll Over on the sroll bar thumb.