--- a/Socket.st	Mon Jan 16 19:56:46 2017 +0000
+++ b/Socket.st	Wed Jan 18 10:02:15 2017 +0000
@@ -3759,7 +3759,6 @@
     "
 ! !
 
-
 !Socket methodsFor:'specials'!
 
 linger:anIntegerOrNil
@@ -4035,6 +4034,14 @@
     ^ self setSocketOption:#'TCP_NODELAY' argument:aBoolean argument:nil.
 ! !
 
+!Socket methodsFor:'testing'!
+
+isSocket
+    "return true, if the receiver is some kind of socket;
+     false returned here - the method is only redefined in Socket."
+
+    ^ true
+! !
 
 !Socket methodsFor:'waiting'!