Raise max RSA keysize (WIP)

@@ -84,11 +84,11 @@
         int             sign;   /* 1 for nonnegative, -1 for negative  */
         int             malloced; /* 1 if value was malloced, 0 if not */
         BIG_CHUNK_TYPE *value;
 } BIGNUM;
 
-#define BIGTMPSIZE 65
+#define BIGTMPSIZE 257
 
 #define BIG_TRUE 1
 #define BIG_FALSE 0
 
 typedef int BIG_ERR_CODE;