diff --git a/tests/pjsua/scripts-recvfrom/209a_reg_handle_423_ok.py b/tests/pjsua/scripts-recvfrom/209a_reg_handle_423_ok.py
new file mode 100644
index 0000000..16ec214
--- /dev/null
+++ b/tests/pjsua/scripts-recvfrom/209a_reg_handle_423_ok.py
@@ -0,0 +1,31 @@
+# $Id$
+import inc_sip as sip
+import inc_sdp as sdp
+
+pjsua = "--null-audio --id=sip:CLIENT --registrar sip:127.0.0.1:$PORT " + \
+	"--realm=python --user=username --password=password " + \
+	"--auto-update-nat=0"
+
+# 423 Response without Min-Expires header
+req1 = sip.RecvfromTransaction("Initial request", 423,
+				include=["REGISTER sip"], 
+				exclude=[],
+				resp_hdr=[]
+			  	)
+
+# Client should retry with Expires header containing special value (pjsip specific)
+req2 = sip.RecvfromTransaction("REGISTER retry after 423 response without Min-Expires header", 423,
+				include=["REGISTER sip", "Expires: 3601"], 
+				exclude=[],
+				resp_hdr=["Min-Expires: 3612"]
+			  	)
+
+# Client should retry with proper Expires header now
+req3 = sip.RecvfromTransaction("REGISTER retry after proper 423", 200,
+				include=["Expires: 3612"], 
+				exclude=[],
+				expect="registration success"
+			  	)
+
+recvfrom_cfg = sip.RecvfromCfg("Reregistration after 423 response",
+			       pjsua, [req1, req2, req3])
diff --git a/tests/pjsua/scripts-recvfrom/209b_reg_handle_423_bad_min_expires1.py b/tests/pjsua/scripts-recvfrom/209b_reg_handle_423_bad_min_expires1.py
new file mode 100644
index 0000000..83a4074
--- /dev/null
+++ b/tests/pjsua/scripts-recvfrom/209b_reg_handle_423_bad_min_expires1.py
@@ -0,0 +1,20 @@
+# $Id$
+import inc_sip as sip
+import inc_sdp as sdp
+
+pjsua = "--null-audio --id=sip:CLIENT --registrar sip:127.0.0.1:$PORT " + \
+	"--realm=python --user=username --password=password " + \
+	"--auto-update-nat=0 --reg-timeout 300"
+
+# 423 Response with Min-Expires header that is lower than what the client
+# had requested
+req1 = sip.RecvfromTransaction("Initial request", 423,
+				include=["REGISTER sip"], 
+				exclude=[],
+				resp_hdr=["Min-Expires: 250"],
+				expect="invalid Min-Expires"
+
+			  	)
+
+recvfrom_cfg = sip.RecvfromCfg("Invalid 423 response to REGISTER",
+			       pjsua, [req1])
diff --git a/tests/pjsua/scripts-recvfrom/209c_reg_handle_423_bad_min_expires2.py b/tests/pjsua/scripts-recvfrom/209c_reg_handle_423_bad_min_expires2.py
new file mode 100644
index 0000000..378ea28
--- /dev/null
+++ b/tests/pjsua/scripts-recvfrom/209c_reg_handle_423_bad_min_expires2.py
@@ -0,0 +1,25 @@
+# $Id$
+import inc_sip as sip
+import inc_sdp as sdp
+
+pjsua = "--null-audio --id=sip:CLIENT --registrar sip:127.0.0.1:$PORT " + \
+	"--realm=python --user=username --password=password " + \
+	"--auto-update-nat=0 --reg-timeout 300"
+
+# 423 without Min-Expires. PJSIP would retry with Expires: 3601
+req1 = sip.RecvfromTransaction("Initial request", 423,
+				include=["REGISTER sip"], 
+				exclude=[],
+				resp_hdr=[]
+			  	)
+
+# Another 423, still without Min-Expires
+req2 = sip.RecvfromTransaction("Retry with guessed Expires header", 423,
+				include=["REGISTER sip", "Expires: 3601"], 
+				exclude=[],
+				resp_hdr=[],
+				expect="without Min-Expires header is invalid"
+			  	)
+
+recvfrom_cfg = sip.RecvfromCfg("Invalid 423 response to REGISTER",
+			       pjsua, [req1, req2])