--- srtp/srtp.c	(libSRTP 2.2.0, the release)
+++ srtp/srtp.c	(working copy)
@@ -1259,11 +1259,6 @@ srtp_stream_init
     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 */
@@ -2221,7 +2216,7 @@ srtp_protect_mki
         status = srtp_rdbx_check(&stream->rtp_rdbx, delta);
         if (status) {
             if (status != srtp_err_status_replay_fail ||
-                !stream->allow_repeat_tx)
+                !(stream->allow_repeat_tx & 0x01))
                 return status; /* we've been asked to reuse an index */
         }
         srtp_rdbx_add_index(&stream->rtp_rdbx, delta);
@@ -2277,10 +2272,23 @@ srtp_protect_mki
     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
@@ -2377,12 +2385,14 @@ srtp_unprotect_mki
     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;
@@ -2531,9 +2541,14 @@ srtp_unprotect_mki
 
 /* 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
 
@@ -2578,6 +2593,7 @@
      * 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
@@ -2605,8 +2621,12 @@
                                   *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));
@@ -2615,8 +2635,14 @@
         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;
+            }
+        }
     }
 
     /*