diff -up at-3.1.12/at.c.nowrap at-3.1.12/at.c
--- at-3.1.12/at.c.nowrap	2010-02-12 12:48:23.000000000 +0100
+++ at-3.1.12/at.c	2010-02-12 12:51:18.781921727 +0100
@@ -308,9 +308,12 @@ writefile(time_t runtimer, char queue)
 	    if (*ap == ' ')
 		*ap = '0';
 
-	if (stat(atfile, &statbuf) != 0)
+	if (stat(atfile, &statbuf) != 0) {
 	    if (errno != ENOENT)
 		perr("Cannot access " ATJOB_DIR);
+	} else {
+	    perr("atjob file already exists; bailing");
+	}
 
 	/* Create the file. The x bit is only going to be set after it has
 	 * been completely written out, to make sure it is not executed in the