--- srtp/srtp.c	(libSRTP 2.1.0, the release)
+++ srtp/srtp.c	(working copy)
@@ -1241,11 +1241,6 @@
    srtp_rdb_init(&srtp->rtcp_rdb);
 
    /* initialize allow_repeat_tx */
-   /* guard against uninitialized memory: allow only 0 or 1 here */
-   if (p->allow_repeat_tx != 0 && p->allow_repeat_tx != 1) {
-     srtp_rdbx_dealloc(&srtp->rtp_rdbx);
-     return srtp_err_status_bad_param;
-   }
    srtp->allow_repeat_tx = p->allow_repeat_tx;
 
    /* DAM - no RTCP key limit at present */
@@ -2187,7 +2182,7 @@
   } else {
     status = srtp_rdbx_check(&stream->rtp_rdbx, delta);
     if (status) {
-      if (status != srtp_err_status_replay_fail || !stream->allow_repeat_tx)
+      if (status != srtp_err_status_replay_fail || !(stream->allow_repeat_tx & 0x01))
         return status; /* we've been asked to reuse an index */
     }
     srtp_rdbx_add_index(&stream->rtp_rdbx, delta);
@@ -2239,11 +2234,23 @@
    if (status)
      return srtp_err_status_cipher_fail;
 
-   /* shift est, put into network byte order */
+   /* shift est, put into network byte order (part 1) */
+#ifdef NO_64BIT_MATH
+   est = make64((high32(est) << 16) | (low32(est) >> 16), low32(est) << 16);
+#endif
+
+   /* Nokia Symbian/S60 requires little-endian ROC */
+   if (stream->allow_repeat_tx & 0x02) {
 #ifdef NO_64BIT_MATH
-   est = be64_to_cpu(make64((high32(est) << 16) |
-						 (low32(est) >> 16),
-						 low32(est) << 16));
+   est = make64(bswap_32(high32(est)), low32(est));
+#else
+   est = (((srtp_xtd_seq_num_t) bswap_32(est >> 16)) << 16) | (est & 0xffff);
+#endif
+   }
+
+   /* shift est, put into network byte order (part 2) */
+#ifdef NO_64BIT_MATH
+   est = be64_to_cpu(est);
 #else
    est = be64_to_cpu(est << 16);
 #endif
@@ -2336,12 +2343,14 @@
   unsigned int enc_octet_len = 0;/* number of octets in encrypted portion */
   uint8_t *auth_tag = NULL; /* location of auth_tag within packet     */
   srtp_xtd_seq_num_t est;        /* estimated xtd_seq_num_t of *hdr        */
+  srtp_xtd_seq_num_t est_roc_le; /* see est; here, ROC is in little-endian */
   int delta;                /* delta of local pkt idx and that in hdr */
   v128_t iv;
   srtp_err_status_t status;
   srtp_stream_ctx_t *stream;
   uint8_t tmp_tag[SRTP_MAX_TAG_LEN];
   uint32_t tag_len, prefix_len;
+  int retry = 0;
   srtp_hdr_xtnd_t *xtn_hdr = NULL;
   unsigned int mki_size = 0;
   srtp_session_keys_t *session_keys = NULL;
@@ -2494,10 +2503,15 @@
 
   /* shift est, put into network byte order */
 #ifdef NO_64BIT_MATH
+  est_roc_le = make64((high32(est) << 16) | (low32(est) >> 16), low32(est) << 16);
+  est_roc_le = make64(bswap_32(high32(est_roc_le)), low32(est_roc_le));
+  est_roc_le = be64_to_cpu(est_roc_le);
   est = be64_to_cpu(make64((high32(est) << 16) |
 					    (low32(est) >> 16),
 					    low32(est) << 16));
 #else
+  est_roc_le = (((srtp_xtd_seq_num_t) bswap_32(est >> 16)) << 16) | (est & 0xffff);
+  est_roc_le = be64_to_cpu(est_roc_le << 16);
   est = be64_to_cpu(est << 16);
 #endif
 
@@ -2541,7 +2555,7 @@
    * function and compare the result with the value of the auth_tag
    */
   if (auth_start) {        
-
+tryagain:
     /* 
      * if we're using a universal hash, then we need to compute the
      * keystream prefix for encrypting the universal hash output
@@ -2568,7 +2582,11 @@
 			 *pkt_octet_len - tag_len - mki_size);
 
     /* run auth func over ROC, then write tmp tag */
-    status = srtp_auth_compute(session_keys->rtp_auth, (uint8_t *)&est, 4, tmp_tag);
+    /* Nokia Symbian/S60 calculates auth_tag with little-endian ROC */
+    if (retry == 0)
+      status = srtp_auth_compute(session_keys->rtp_auth, (uint8_t *)&est, 4, tmp_tag);
+    else
+      status = srtp_auth_compute(session_keys->rtp_auth, (uint8_t *)&est_roc_le, 4, tmp_tag);
 
     debug_print(mod_srtp, "computed auth tag:    %s", 
 		srtp_octet_string_hex_string(tmp_tag, tag_len));
@@ -2577,8 +2595,15 @@
     if (status)
       return srtp_err_status_auth_fail;   
 
-    if (octet_string_is_eq(tmp_tag, auth_tag, tag_len))
-      return srtp_err_status_auth_fail;
+    if (octet_string_is_eq(tmp_tag, auth_tag, tag_len)) {
+      if (retry == 0) {
+        retry = 1;
+        goto tryagain;
+      }
+      else {
+        return srtp_err_status_auth_fail;
+      }
+    }
   }
 
   /*