--- a/Context.st	Tue Apr 14 13:04:28 2015 +0200
+++ b/Context.st	Tue Apr 14 21:44:09 2015 +0200
@@ -360,8 +360,7 @@
     "/ some machines have the arguments/receiver etc. kept in register vars ...
     "/ the unfix updates the machine-stack version of the receiver.
 %{
-#ifdef __JAVA__
-#else
+#ifndef __JAVA__
     __UNFIXCONTEXT(self, 0);
 #endif
 %}.
@@ -394,7 +393,19 @@
 
 %{
 #ifdef __JAVA__
-    ERROR("unimplemented");
+    {
+	int idx = context.stArg(0).intValue("[instVarAt:]");
+
+	if (idx == I_sender) {
+	    return context._RETURN( ((STContext)self).currentContinuation.caller() );
+	}
+	if (idx == I_retvalTemp) {
+	    return context._RETURN( Nil );
+	}
+	if (idx == I_handle) {
+	    return context._RETURN( Nil );
+	}
+    }
 #else
     if (index == __MKSMALLINT(__SLOT_CONTEXT_SENDER)) {                 // sender - must be accessed specially
 	 what = @symbol(sender);
@@ -405,6 +416,9 @@
     }
 #endif
 %}.
+    what == #sender ifTrue:[
+	^ self sender
+    ].
     ^ super instVarAt:index
 !
 
@@ -432,7 +446,7 @@
     "/ some machines have the arguments kept in register vars ...
     "/ the unfix updates the machine-stack version of the receiver.
 %{
-#ifdef __JAVA__
+#ifndef __JAVA__
     __UNFIXCONTEXT(self, 0);
 #endif
 %}.
@@ -2798,11 +2812,11 @@
 !Context class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic/Context.st,v 1.211 2015-04-07 20:17:36 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/Context.st,v 1.212 2015-04-14 19:44:09 cg Exp $'
 !
 
 version_CVS
-    ^ '$Header: /cvs/stx/stx/libbasic/Context.st,v 1.211 2015-04-07 20:17:36 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/Context.st,v 1.212 2015-04-14 19:44:09 cg Exp $'
 !
 
 version_HG