The fix for 4521075 that went back to 5.0 update 5 added a new optional system property, "sun.swing.enableImprovedDragGesture" (optional meaning that licensees are not required to implement it). This property (which does not exist in 6.0) is used in 5.0 to enable the fix for a very popular bug. The bug was the fifth highest vote getter on the JDC with 239 votes.

Please add this property to Java Web Start's list of trusted properties for the next 5.0 update release.