There is a difference in key event between 5.0 and mustang dev builds. When you type ctrl+alt+s, you will get different value in keyChar attribute:
JDK1.5: java.awt.event.KeyEvent[keyChar='s']
JDK1.6: java.awt.event.KeyEvent[keyChar='^S']

All other attributes in event are the same, i.e. modifiers are Ctrl+Alt etc.

To reproduce the issue you can try to use the JEP application from here:
http://editor.netbeans.org/doc/KeyboardIssues/KeyboardIssues.html

The JEP application prints events which occur on individual key strokes to console.

For more details see also NetBeans bug 60874:
http://www.netbeans.org/issues/show_bug.cgi?id=60874