openjdk update and rxtx

[Warren Block]

After updating openjdk6, comms/rxtx gave an exception when devel/arduino 
tried to use it.

Rebuilding comms/rxtx solved it.  Don't know why portmaster didn't see 
that.

% arduino
Exception in thread "main" java.lang.NoClassDefFoundError: gnu/io/CommPortIdentifier
 	at processing.app.Editor.populateSerialMenu(Editor.java:969)
 	at processing.app.Editor.buildToolsMenu(Editor.java:697)
 	at processing.app.Editor.buildMenuBar(Editor.java:482)
 	at processing.app.Editor.<init>(Editor.java:204)
 	at processing.app.Base.handleOpen(Base.java:700)
 	at processing.app.Base.handleOpen(Base.java:665)
 	at processing.app.Base.handleNew(Base.java:561)
 	at processing.app.Base.<init>(Base.java:301)
 	at processing.app.Base.main(Base.java:190)
Caused by: java.lang.ClassNotFoundException: gnu.io.CommPortIdentifier
 	at java.net.URLClassLoader$1.run(URLClassLoader.java:217)
 	at java.security.AccessController.doPrivileged(Native Method)
 	at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
 	at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
 	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
 	at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
 	... 9 more