Added reference to jbuf (now declared in signal_handler.c)

src/frontend/signal_handler.h

@@ -1,6 +1,7 @@
 /*************
  * Header file for signal_handler.c
  * 1999 E. Rouat
+ * $Id$
  ************/
 
 #ifndef SIGNAL_HANDLER_H_INCLUDED
@@ -15,4 +16,6 @@ RETSIGTYPE sigbus(void);
 RETSIGTYPE sigsegv(void);
 RETSIGTYPE sig_sys(void);
 
+extern JMP_BUF jbuf;
+
 #endif