--- php-5.2.17/ext/standard/crypt.c~	2013-03-25 17:26:27.000000000 +0100
+++ php-5.2.17/ext/standard/crypt.c	2013-03-25 17:27:42.866436012 +0100
@@ -118,6 +118,7 @@
    Encrypt a string */
 PHP_FUNCTION(crypt)
 {
+	char *crypt_res;
 	char salt[PHP_MAX_SALT_LEN+1];
 	char *str, *salt_in = NULL;
 	int str_len, salt_in_len;
@@ -163,7 +163,12 @@
 		RETURN_STRING(crypt_r(str, salt, &buffer), 1);
 	}
 #else
-	RETURN_STRING(crypt(str, salt), 1);
+	crypt_res = crypt(str, salt);
+	if (!crypt_res) {
+		RETURN_FALSE;
+	} else {
+		RETURN_STRING(crypt_res, 1);
+	}
 #endif
 }
 /* }}} */