diff --git a/callagent/tests/SIPCallAgentTest.st b/callagent/tests/SIPCallAgentTest.st
index 6e56fd4..ff62780 100644
--- a/callagent/tests/SIPCallAgentTest.st
+++ b/callagent/tests/SIPCallAgentTest.st
@@ -34,14 +34,14 @@ TestCase subclass: SIPCallAgentTest [
             contents
     ]
 
-    redirect: aBranch callId: aCallId tag: aTag [
+    redirect: aBranch callId: aCallId tag: aTag cseq: aCseq [
         ^(WriteStream on: String new)
             nextPutAll: 'SIP/2.0 302 Moved Temporarily'; cr; nl;
             nextPutAll: 'Allow: INVITE, ACK'; cr; nl;
             nextPutAll: 'Call-Id: '; nextPutAll: aCallId; cr; nl;
             nextPutAll: 'Contact: sip:+12345678@10.8.254.1'; cr; nl;
             nextPutAll: 'Content-Length: 0'; cr; nl;
-            nextPutAll: 'CSeq: 1 INVITE'; cr; nl;
+            nextPutAll: 'CSeq: '; nextPutAll: aCseq asString; nextPutAll: ' INVITE'; cr; nl;
             nextPutAll: 'Via: SIP/2.0/UDP 127.0.0.1:5060;branch='; nextPutAll: aBranch; cr; nl;
             nextPutAll: 'From: <sip:st@127.0.0.1>;tag='; nextPutAll: aTag; cr; nl;
             nextPutAll: 'To: <sip:st@127.0.0.1>'; cr; nl;
@@ -51,12 +51,12 @@ TestCase subclass: SIPCallAgentTest [
             contents
     ]
 
-    trying: aBranch callId: aCallId tag: aTag [
+    trying: aBranch callId: aCallId tag: aTag cseq: aCseq [
         ^(WriteStream on: String new)
             nextPutAll: 'SIP/2.0 100 Trying'; cr; nl;
             nextPutAll: 'Call-ID: '; nextPutAll: aCallId; cr; nl;
             nextPutAll: 'Content-Length: 0'; cr; nl;
-            nextPutAll: 'CSeq: 1 INVITE'; cr; nl;
+            nextPutAll: 'CSeq: '; nextPutAll: aCseq asString; nextPutAll: ' INVITE'; cr; nl;
             nextPutAll: 'From: <sip:st@127.0.0.1>;tag='; nextPutAll: aTag; cr; nl;
             nextPutAll: 'To: <sip:st@127.0.0.1>'; cr; nl;
             nextPutAll: 'Via: SIP/2.0/UDP 127.0.0.1:5060;branch='; nextPutAll: aBranch; cr; nl;
@@ -77,7 +77,7 @@ TestCase subclass: SIPCallAgentTest [
             contents
     ]
 
-    invalidAuthorizationRequired: aBranch callId: aCallId tag: aTag [
+    invalidAuthorizationRequired: aBranch callId: aCallId tag: aTag cseq: aCseq [
         "This is missing WWW-Authenticate so it is kind of invalid"
         ^(WriteStream on: String new)
             nextPutAll: 'SIP/2.0 401 Unauthorized'; cr; nl;
@@ -85,7 +85,7 @@ TestCase subclass: SIPCallAgentTest [
             nextPutAll: 'From: <sip:st@127.0.0.1>;tag='; nextPutAll: aTag; cr; nl;
             nextPutAll: 'To: <sip:st@127.0.0.1>'; cr; nl;
             nextPutAll: 'Call-ID: '; nextPutAll: aCallId; cr; nl;
-            nextPutAll: 'CSeq: 1 INVITE'; cr; nl;
+            nextPutAll: 'CSeq: '; nextPutAll: aCseq asString; nextPutAll: ' INVITE'; cr; nl;
             nextPutAll: 'Server: YATE/5.1.0'; cr; nl;
             nextPutAll: 'Allow: ACK, INVITE, BYE, CANCEL, REGISTER, REFER'; cr; nl;
             nextPutAll: 'Content-Length: 0'; cr; nl;
@@ -93,10 +93,6 @@ TestCase subclass: SIPCallAgentTest [
             contents
     ]
 
-    authorizationRequired: aBranch callId: aCallId tag: aTag [
-        ^self authorizationRequired: aBranch callId: aCallId tag: aTag cseq: 1
-    ]
-
     authorizationRequired: aBranch callId: aCallId tag: aTag cseq: aCseq [
         ^(WriteStream on: String new)
             nextPutAll: 'SIP/2.0 401 Unauthorized'; cr; nl;
@@ -141,21 +137,22 @@ TestCase subclass: SIPCallAgentTest [
     ]
 
     testSimpleInvite [
-        | call msg |
+        | call msg cseq |
         call := SIPCall fromUser: 'sip:sip@test' host: '127.0.0.1' port: 5060 to: 'sip:127.0.0.1' on: agent.
         call createCall: 'dummy-sdp'.
         self assert: call state equals: SIPCall stateInvite.
         self assert: sent size equals: 1.
         msg := agent parser parse: sent first data.
         self assert: msg class verb equals: SIPInviteRequest verb.
-        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: 1.
+        cseq := (msg parameter: 'CSeq' ifAbsent: [-1]) number.
+        self assert: cseq >= 0.
 
         call cancel.
         self assert: call state equals: SIPCall stateCancel.
     ]
 
     testInviteWithInvalidAuthorization [
-        | call msg branch callId fromTag auth |
+        | call msg branch callId fromTag auth cseq |
  
         call := SIPCall fromUser: 'sip:sip@test' host: '127.0.0.1' port: 5060 to: 'sip:127.0.0.1' on: agent.
         call createCall: 'dummy-sdp'.
@@ -163,20 +160,21 @@ TestCase subclass: SIPCallAgentTest [
         "First assertions for the invite"
         self assert: sent size equals: 1.
         msg := agent parser parse: sent first data.
-        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: 1.
+        cseq := (msg parameter: 'CSeq' ifAbsent: [-1]) number.
+        self assert: cseq >= 0.
         self assert: call state equals: SIPCall stateInvite.
 
         "Now inject an auth requirement message"
         branch := (msg parameter: 'Via' ifAbsent: [nil]) branch.
         callId := (msg parameter: 'Call-ID' ifAbsent: [-1]).
         fromTag := (msg parameter: 'From' ifAbsent: [nil]).
-        transport inject: (self invalidAuthorizationRequired: branch callId: callId tag: fromTag tag).
+        transport inject: (self invalidAuthorizationRequired: branch callId: callId tag: fromTag tag cseq: cseq).
         self assert: call state equals: SIPCall stateFailed.
         self assert: sent size equals: 1.
     ]
 
     testInviteWithAuthorization [
-        | call msg branch callId fromTag auth secondBranch |
+        | call msg branch callId fromTag auth secondBranch cseq |
 
         call := SIPCall fromUser: 'sip:sip@test' host: '127.0.0.1' port: 5060 to: 'sip:127.0.0.1' on: agent.
         call createCall: 'dummy-sdp'.
@@ -184,14 +182,15 @@ TestCase subclass: SIPCallAgentTest [
         "First assertions for the invite"
         self assert: sent size equals: 1.
         msg := agent parser parse: sent first data.
-        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: 1.
+        cseq := (msg parameter: 'CSeq' ifAbsent: [-1]) number.
+        self assert: cseq >= 0.
         self assert: call state equals: SIPCall stateInvite.
 
         "Now inject an auth requirement message"
         branch := (msg parameter: 'Via' ifAbsent: [nil]) branch.
         callId := (msg parameter: 'Call-ID' ifAbsent: [-1]).
         fromTag := (msg parameter: 'From' ifAbsent: [nil]).
-        transport inject: (self authorizationRequired: branch callId: callId tag: fromTag tag).
+        transport inject: (self authorizationRequired: branch callId: callId tag: fromTag tag cseq: cseq).
 
         "Verify that a second message has been sent and it contains an auth result"
         self assert: sent size equals: 3.
@@ -202,7 +201,7 @@ TestCase subclass: SIPCallAgentTest [
         self assert: msg class verb equals: 'INVITE'.
         secondBranch := (msg parameter: 'Via' ifAbsent: [nil]) branch.
         self deny: branch = secondBranch.
-        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: 2.
+        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: cseq + 1.
         self assert: call state equals: SIPCall stateInvite.
 
         "Verify the auth part of the message"
@@ -219,7 +218,7 @@ TestCase subclass: SIPCallAgentTest [
     ]
 
     testInviteWithDoubleAuth [
-        | call msg branch callId fromTag auth |
+        | call msg branch callId fromTag auth cseq |
 
         call := SIPCall fromUser: 'sip:sip@test' host: '127.0.0.1' port: 5060 to: 'sip:127.0.0.1' on: agent.
         call createCall: 'dummy-sdp'.
@@ -227,14 +226,15 @@ TestCase subclass: SIPCallAgentTest [
         "First assertions for the invite"
         self assert: sent size equals: 1.
         msg := agent parser parse: sent first data.
-        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: 1.
+        cseq := (msg parameter: 'CSeq' ifAbsent: [-1]) number.
+        self assert: cseq >= 0.
         self assert: call state equals: SIPCall stateInvite.
 
         "Now inject an auth requirement message"
         branch := (msg parameter: 'Via' ifAbsent: [nil]) branch.
         callId := (msg parameter: 'Call-ID' ifAbsent: [-1]).
         fromTag := (msg parameter: 'From' ifAbsent: [nil]).
-        transport inject: (self authorizationRequired: branch callId: callId tag: fromTag tag).
+        transport inject: (self authorizationRequired: branch callId: callId tag: fromTag tag cseq: cseq).
 
         "Verify that a second message has been sent and it contains an auth result"
         self assert: sent size equals: 3.
@@ -244,7 +244,7 @@ TestCase subclass: SIPCallAgentTest [
         msg := agent parser parse: sent third data.
         self assert: msg class verb equals: 'INVITE'.
         branch := (msg parameter: 'Via' ifAbsent: [nil]) branch.
-        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: 2.
+        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: cseq + 1.
         self assert: call state equals: SIPCall stateInvite.
 
         "Verify the auth part of the message"
@@ -257,12 +257,12 @@ TestCase subclass: SIPCallAgentTest [
         self assert: auth response equals: 'bc8dfaa413e897863dbab4c622e4b9b4'.
 
         "Inject another auth.."
-        transport inject: (self authorizationRequired: branch callId: callId tag: fromTag tag cseq: 2).
+        transport inject: (self authorizationRequired: branch callId: callId tag: fromTag tag cseq: cseq + 1).
         self assert: call state equals: #failed.
     ]
 
     setUpProxyAuthCall [
-        | call msg branch callId fromTag auth secondBranch origCnonce |
+        | call msg branch callId fromTag auth secondBranch origCnonce cseq |
 
         call := SIPCall fromUser: 'sip:sip@test' host: '127.0.0.1' port: 5060 to: 'sip:127.0.0.1' on: agent.
         call createCall: 'dummy-sdp'.
@@ -270,14 +270,15 @@ TestCase subclass: SIPCallAgentTest [
         "First assertions for the invite"
         self assert: sent size equals: 1.
         msg := agent parser parse: sent first data.
-        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: 1.
+        cseq := (msg parameter: 'CSeq' ifAbsent: [-1]) number.
+        self assert: cseq >= 0.
         self assert: call state equals: SIPCall stateInvite.
 
         "Now inject an auth requirement message"
         branch := (msg parameter: 'Via' ifAbsent: [nil]) branch.
         callId := (msg parameter: 'Call-ID' ifAbsent: [-1]).
         fromTag := (msg parameter: 'From' ifAbsent: [nil]).
-        transport inject: (self proxyAuthRequired: branch callId: callId tag: fromTag tag cseq: 1).
+        transport inject: (self proxyAuthRequired: branch callId: callId tag: fromTag tag cseq: cseq).
 
         "Verify that a second message has been sent and it contains an auth result"
         self assert: sent size equals: 3.
@@ -288,7 +289,7 @@ TestCase subclass: SIPCallAgentTest [
         self assert: msg class verb equals: 'INVITE'.
         secondBranch := (msg parameter: 'Via' ifAbsent: [nil]) branch.
         self deny: branch = secondBranch.
-        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: 2.
+        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: cseq + 1.
         self assert: call state equals: SIPCall stateInvite.
 
         "Verify the auth part of the message"
@@ -307,10 +308,10 @@ TestCase subclass: SIPCallAgentTest [
         origCnonce := auth clientNonce.
 
         "Inject a 200 and check the ACK"
-        transport inject: (self ok: secondBranch callId: callId tag: fromTag tag cseq: 2).
+        transport inject: (self ok: secondBranch callId: callId tag: fromTag tag cseq: cseq + 1).
         self assert: sent size equals: 4.
         msg := agent parser parse: (sent at: 4) data.
-        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: 2.
+        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: cseq + 1.
         self assert: call state equals: SIPCall stateSession.
         auth := msg parameter: 'Proxy-Authorization' ifAbsent: [nil].
         self deny: auth isNil.
@@ -336,18 +337,19 @@ TestCase subclass: SIPCallAgentTest [
     ]
 
     testWithProxyAuthRemoteBye [
-        | call msg branch callId fromTag sentNr |
+        | call msg branch callId fromTag sentNr cseq |
         call := self setUpProxyAuthCall.
 
         msg := agent parser parse: sent second data.
         branch := (msg parameter: 'Via' ifAbsent: [nil]) branch.
         callId := (msg parameter: 'Call-ID' ifAbsent: [-1]).
         fromTag := (msg parameter: 'From' ifAbsent: [nil]).
+        cseq := (msg parameter: 'CSeq' ifAbsent: [-1]) number.
 
         sentNr := sent size.
         self assert: call state equals: SIPCall stateSession.
 
-        transport inject: (self bye: branch callId: callId toTag: fromTag tag cseq: 2).
+        transport inject: (self bye: branch callId: callId toTag: fromTag tag cseq: cseq + 1).
         self assert: sent size equals: sentNr + 1.
         self assert: call state equals: SIPCall stateRemoteHangup.
 
@@ -359,7 +361,7 @@ TestCase subclass: SIPCallAgentTest [
     ]
 
     testInviteWithRedirect [
-        | call msg branch callId fromTag |
+        | call msg branch callId fromTag cseq |
 
         call := SIPCall fromUser: 'sip:sip@test' host: '127.0.0.1' port: 5060 to: 'sip:127.0.0.1' on: agent.
         call createCall: 'dummy-sdp'.
@@ -367,18 +369,19 @@ TestCase subclass: SIPCallAgentTest [
         "First assertions for the invite"
         self assert: sent size equals: 1.
         msg := agent parser parse: sent first data.
-        self assert: (msg parameter: 'CSeq' ifAbsent: [-1]) number equals: 1.
+        cseq := (msg parameter: 'CSeq' ifAbsent: [-1]) number.
+        self assert: cseq >= 0.
         self assert: call state equals: SIPCall stateInvite.
         branch := (msg parameter: 'Via' ifAbsent: [nil]) branch.
         callId := (msg parameter: 'Call-ID' ifAbsent: [-1]).
         fromTag := (msg parameter: 'From' ifAbsent: [nil]).
 
         "Inject a 100 trying"
-        transport inject: (self trying: branch callId: callId tag: fromTag tag).
+        transport inject: (self trying: branch callId: callId tag: fromTag tag cseq: cseq).
         self assert: call state equals: SIPCall stateInvite.
 
         "We could inject a 100 Trying but Now inject an auth requirement message"
-        transport inject: (self redirect: branch callId: callId tag: fromTag tag).
+        transport inject: (self redirect: branch callId: callId tag: fromTag tag cseq: cseq).
         self assert: call state equals: SIPCall stateRedirect.
 
         "Check we get the ACK"