diff -urpN john-1.7.8-jumbo-6a/src/bench.c john-1.7.8-jumbo-6b/src/bench.c
--- john-1.7.8-jumbo-6a/src/bench.c	2011-08-03 16:19:13.000000000 +0000
+++ john-1.7.8-jumbo-6b/src/bench.c	2011-09-08 19:35:08.828125000 +0000
@@ -82,9 +82,12 @@ static void bench_handle_timer(int signu
 static void bench_set_keys(struct fmt_main *format,
 	struct fmt_tests *current, int cond)
 {
-	char *plaintext;
+	char *_plaintext;
+	static char *plaintext;
 	int index, length;
 
+	if (!plaintext) plaintext = mem_alloc_tiny(4096, MEM_ALIGN_WORD);
+
 	format->methods.clear_keys();
 
 	length = format->params.benchmark_length;
@@ -92,7 +95,9 @@ static void bench_set_keys(struct fmt_ma
 		do {
 			if (!current->ciphertext)
 				current = format->params.tests;
-			plaintext = current->plaintext;
+			_plaintext = current->plaintext;
+			strcpy(plaintext, _plaintext);
+			*plaintext ^= 0x22;
 			current++;
 
 			if (cond > 0) {