From: <glassfish_at_javadesktop.org>
Date: Tue, 05 Oct 2010 20:47:40 PDT

Its available in admin GUI :
eg:
Left pane : Resources > JDBC > JDBC Connection Pools > Click "Derby Pool"
Right pane : select the tab "Advanced",
Section : "Connection Settings"
Attribute : "Leak-timeout"
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