diff -rupN rxtx-2.2pre2/src/gnu/io/RXTXCommDriver.java rxtx-2.2pre2.new/src/gnu/io/RXTXCommDriver.java
--- rxtx-2.2pre2/src/gnu/io/RXTXCommDriver.java	2008-11-13 16:44:01.000000000 -0800
+++ rxtx-2.2pre2.new/src/gnu/io/RXTXCommDriver.java	2015-08-21 16:19:14.330743949 -0700
@@ -579,6 +579,7 @@ public class RXTXCommDriver implements C
 						"ttyUSB", // for USB frobs
 						"rfcomm",       // bluetooth serial device
 						"ttyircomm", // linux IrCommdevices (IrDA serial emu)
+						"ttyACM" // linux CDC ACM devices
 						};
 						CandidatePortPrefixes=Temp;
 					}