diff -urp john-1.7.8/run/john.conf john-1.7.8-external-events/run/john.conf
--- john-1.7.8/run/john.conf	2011-05-23 01:19:14 +0000
+++ john-1.7.8-external-events/run/john.conf	2011-09-12 22:55:06 +0000
@@ -1244,3 +1244,10 @@ void filter()
 	word[i--] = 0;
 	word[i] = map2[(o & 0xfff) + (e >> 12)];
 }
+
+[List.External:TestAbort]
+void filter()
+{
+	if (word[0] == 'a')
+		event_pending = event_abort = 1;
+}
diff -urp john-1.7.8/src/external.c john-1.7.8-external-events/src/external.c
--- john-1.7.8/src/external.c	2006-02-27 03:58:02 +0000
+++ john-1.7.8-external-events/src/external.c	2011-09-12 22:51:24 +0000
@@ -12,6 +12,7 @@
 #include "compiler.h"
 #include "loader.h"
 #include "logger.h"
+#include "signals.h"
 #include "status.h"
 #include "recovery.h"
 #include "config.h"
@@ -24,8 +25,20 @@ char *ext_mode = NULL;
 
 static c_int ext_word[PLAINTEXT_BUFFER_SIZE];
 
-static struct c_ident ext_globals = {
+static struct c_ident ext_event_pending = {
 	NULL,
+	"event_pending",
+	(int *)&event_pending
+};
+
+static struct c_ident ext_event_abort = {
+	&ext_event_pending,
+	"event_abort",
+	(int *)&event_abort
+};
+
+static struct c_ident ext_globals = {
+	&ext_event_abort,
 	"word",
 	ext_word
 };