diff --git a/lib/telnet.c b/lib/telnet.c
index dd93f3530..155d4b260 100644
--- a/lib/telnet.c
+++ b/lib/telnet.c
@@ -1220,43 +1220,63 @@ CURLcode telrcv(struct connectdata *conn,
 }
 
 /* Escape and send a telnet data block */
-/* TODO: write large chunks of data instead of one byte at a time */
 static CURLcode send_telnet_data(struct connectdata *conn,
                                  char *buffer, ssize_t nread)
 {
-  unsigned char outbuf[2];
-  ssize_t bytes_written, total_written;
-  int out_count;
+  ssize_t escapes, i, j, outlen;
+  unsigned char *outbuf = NULL;
   CURLcode result = CURLE_OK;
+  ssize_t bytes_written, total_written;
 
-  while(!result && nread--) {
-    outbuf[0] = *buffer++;
-    out_count = 1;
-    if(outbuf[0] == CURL_IAC)
-      outbuf[out_count++] = CURL_IAC;
+  /* Determine size of new buffer after escaping */
+  escapes = 0;
+  for(i = 0; i < nread; i++)
+    if((unsigned char)buffer[i] == CURL_IAC)
+      escapes++;
+  outlen = nread + escapes;
 
-    total_written = 0;
-    do {
-      /* Make sure socket is writable to avoid EWOULDBLOCK condition */
-      struct pollfd pfd[1];
-      pfd[0].fd = conn->sock[FIRSTSOCKET];
-      pfd[0].events = POLLOUT;
-      switch(Curl_poll(pfd, 1, -1)) {
-        case -1:                    /* error, abort writing */
-        case 0:                     /* timeout (will never happen) */
-          result = CURLE_SEND_ERROR;
-          break;
-        default:                    /* write! */
-          bytes_written = 0;
-          result = Curl_write(conn, conn->sock[FIRSTSOCKET],
-                              outbuf+total_written, out_count-total_written,
-                              &bytes_written);
-          total_written += bytes_written;
-          break;
-      }
-      /* handle partial write */
-    } while(!result && total_written < out_count);
+  if(outlen == nread)
+    outbuf = (unsigned char *)buffer;
+  else {
+    outbuf = malloc(nread + escapes + 1);
+    if(!outbuf)
+      return CURLE_OUT_OF_MEMORY;
+
+    j = 0;
+    for(i = 0; i < nread; i++) {
+      outbuf[j++] = buffer[i];
+      if((unsigned char)buffer[i] == CURL_IAC)
+        outbuf[j++] = CURL_IAC;
+    }
+    outbuf[j] = '\0';
   }
+
+  total_written = 0;
+  while(!result && total_written < outlen) {
+    /* Make sure socket is writable to avoid EWOULDBLOCK condition */
+    struct pollfd pfd[1];
+    pfd[0].fd = conn->sock[FIRSTSOCKET];
+    pfd[0].events = POLLOUT;
+    switch(Curl_poll(pfd, 1, -1)) {
+      case -1:                    /* error, abort writing */
+      case 0:                     /* timeout (will never happen) */
+        result = CURLE_SEND_ERROR;
+        break;
+      default:                    /* write! */
+        bytes_written = 0;
+        result = Curl_write(conn, conn->sock[FIRSTSOCKET],
+                            outbuf + total_written,
+                            outlen - total_written,
+                            &bytes_written);
+        total_written += bytes_written;
+        break;
+    }
+  }
+
+  /* Free malloc copy if escaped */
+  if(outbuf != (unsigned char *)buffer)
+    free(outbuf);
+
   return result;
 }
 
diff --git a/tests/data/Makefile.inc b/tests/data/Makefile.inc
index 9e573f6aa..94439bccd 100644
--- a/tests/data/Makefile.inc
+++ b/tests/data/Makefile.inc
@@ -146,7 +146,7 @@ test1364 test1365 test1366 test1367 test1368 test1369 test1370 test1371 \
 test1372 test1373 test1374 test1375 test1376 test1377 test1378 test1379 \
 test1380 test1381 test1382 test1383 test1384 test1385 test1386 test1387 \
 test1388 test1389 test1390 test1391 test1392 test1393 test1394 test1395 \
-test1396 test1397 test1398 \
+test1396 test1397 test1398 test1399 \
 \
 test1400 test1401 test1402 test1403 test1404 test1405 test1406 test1407 \
 test1408 test1409 test1410 test1411 test1412 test1413 test1414 test1415 \
diff --git a/tests/data/test1399 b/tests/data/test1399
new file mode 100644
index 000000000..830960532
--- /dev/null
+++ b/tests/data/test1399
@@ -0,0 +1,43 @@
+<testcase>
+<info>
+<keywords>
+TELNET
+UPLOAD
+</keywords>
+</info>
+
+#
+# Server-side
+<reply>
+</reply>
+
+#
+# Client-side
+<client>
+<server>
+http
+</server>
+<features>
+telnet
+</features>
+<name>
+TELNET check stdin to HTTP
+</name>
+<stdin>
+GET /we/want/1399 HTTP/1.0
+
+</stdin>
+<command option="no-output">
+telnet://%HOSTIP:%HTTPPORT
+</command>
+</client>
+
+#
+# Verify data after the test has been "shot"
+<verify>
+<protocol>
+GET /we/want/1399 HTTP/1.0
+
+</protocol>
+</verify>
+</testcase>