diff --git a/openbsc/contrib/rtp/rtp_replay_sip.st b/openbsc/contrib/rtp/rtp_replay_sip.st
new file mode 100644
index 0000000..5f844df
--- /dev/null
+++ b/openbsc/contrib/rtp/rtp_replay_sip.st
@@ -0,0 +1,87 @@
+"""
+Create a SIP connection and then stream...
+"""
+
+PackageLoader
+    fileInPackage: #OsmoSIP.
+
+"Load for the replay code"
+FileStream fileIn: 'rtp_replay_shared.st'.
+
+
+Osmo.SIPCall subclass: StreamCall [
+    | sem stream |
+
+    createCall: aSDP [
+        | sdp |
+        stream := RTPReplay on: 'rtp_ssrc6976010.240.240.1_to_10.240.240.50.state'.
+        sdp := aSDP % {stream localPort}.
+        ^ super createCall: sdp.
+    ]
+
+    sem: aSemaphore [
+          sem := aSemaphore
+    ]
+
+    sessionNew [
+        | host port |
+        Transcript nextPutAll: 'The call has started'; nl.
+        Transcript nextPutAll: sdp_result; nl.
+
+        host := SDPUtils findHost: sdp_result.
+        port := SDPUtils findPort: sdp_result.
+
+        [
+            stream streamAudio: host port: port.
+            Transcript nextPutAll: 'Streaming has finished.'; nl.
+        ] fork.
+    ]
+
+    sessionFailed [
+        sem signal
+    ]
+
+    sessionEnd [
+        sem signal
+    ]
+]
+
+Eval [
+    | transport agent call sem sdp_fr sdp_amr |
+
+
+    sdp_fr := (WriteStream on: String new)
+        nextPutAll: 'v=0'; cr; nl;
+        nextPutAll: 'o=twinkle 1739517580 1043400482 IN IP4 127.0.0.1'; cr; nl;
+        nextPutAll: 's=-'; cr; nl;
+        nextPutAll: 'c=IN IP4 127.0.0.1'; cr; nl;
+        nextPutAll: 't=0 0'; cr; nl;
+        nextPutAll: 'm=audio %1 RTP/AVP 0 101'; cr; nl;
+        nextPutAll: 'a=rtpmap:0 PCMU/8000'; cr; nl;
+        nextPutAll: 'a=rtpmap:101 telephone-event/8000'; cr; nl;
+        nextPutAll: 'a=fmtp:101 0-15'; cr; nl;
+        nextPutAll: 'a=ptime:20'; cr; nl;
+        contents.
+
+    sem := Semaphore new.
+    transport := Osmo.SIPUdpTransport
+          startOn: '0.0.0.0' port: 5066.
+    agent := Osmo.SIPUserAgent createOn: transport.
+    transport start.
+
+    call := (StreamCall
+              fromUser: 'sip:1000@sip.zecke.osmocom.org'
+              host: '127.0.0.1'
+              port: 5060
+              to: 'sip:123456@127.0.0.1'
+              on: agent)
+              sem: sem; yourself.
+
+    call createCall: sdp_fr.
+
+
+    "Wait for the stream to have ended"
+    sem wait.
+
+    (Delay forSeconds: 4) wait.
+]