diff --git a/CHANGES b/CHANGES
index abbbcb6ff9..655a1419d3 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,4 +1,9 @@
 
+2.4-572 | 2016-05-23 12:45:23 -0700
+
+  * Fix for a table refering to a expire function that's not defined.
+    Addresses BIT-1597. (Robin Sommer)
+
 2.4-571 | 2016-05-23 08:26:43 -0700
 
   * Fixing a few Coverity warnings. (Robin Sommer)
diff --git a/VERSION b/VERSION
index b15074dfd9..bd4866e283 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-2.4-571
+2.4-572
diff --git a/src/Val.cc b/src/Val.cc
index f008c63787..6b63922575 100644
--- a/src/Val.cc
+++ b/src/Val.cc
@@ -2285,8 +2285,23 @@ double TableVal::CallExpireFunc(Val* idx)
 
 	try
 		{
-		Val* vs = expire_expr->Eval(0)->AsFunc()->Call(vl);
+		Val* vf = expire_expr->Eval(0);
+
+		if ( ! vf )
+			// Will have been reported already.
+			return 0;
+
+		if ( vf->Type()->Tag() != TYPE_FUNC )
+			{
+			Unref(vf);
+			vf->Error("not a function");
+			return 0;
+			}
+
+		Val* vs = vf->AsFunc()->Call(vl);
 		secs = vs->AsInterval();
+
+		Unref(vf);
 		Unref(vs);
 		delete vl;
 		}
diff --git a/testing/btest/Baseline/language.expire-func-undef/output b/testing/btest/Baseline/language.expire-func-undef/output
new file mode 100644
index 0000000000..05b71a9908
--- /dev/null
+++ b/testing/btest/Baseline/language.expire-func-undef/output
@@ -0,0 +1,20 @@
+1299470395.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299470405.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299473995.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299474005.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299477595.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299477605.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299481195.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299481205.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299484795.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299484805.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299488395.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299488405.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299491995.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299492005.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299495595.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299495605.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299499195.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299499205.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+1299502795.000000 error in /home/robin/bro/master/testing/btest/.tmp/language.expire-func-undef/expire-func-undef.bro, line 12: value used but not set (segfault::scan_summary)
+orig: 10.0.0.2: peers: {\x0a\x0910.0.0.3\x0a}
diff --git a/testing/btest/language/expire-func-undef.bro b/testing/btest/language/expire-func-undef.bro
new file mode 100644
index 0000000000..1184cd2bf2
--- /dev/null
+++ b/testing/btest/language/expire-func-undef.bro
@@ -0,0 +1,40 @@
+# @TEST-EXEC: bro -r $TRACES/rotation.trace -b %INPUT >output 2>&1
+# @TEST-EXEC: btest-diff output
+
+module segfault; 
+
+export {
+
+        global scan_summary:
+                function(t: table[addr] of set[addr], orig: addr): interval;
+
+        global distinct_peers: table[addr] of set[addr]
+                &read_expire = 7 secs &expire_func=scan_summary &redef;
+
+} 
+
+
+event new_connection(c: connection)
+{ 
+
+	local orig = c$id$orig_h ;
+	local resp = c$id$resp_h ; 
+
+
+	if (orig !in distinct_peers)
+		distinct_peers[orig]=set(); 
+	
+	if (resp !in distinct_peers[orig]) 
+		add distinct_peers[orig][resp]; 
+
+} 
+
+event bro_done()
+{
+
+	for (o in distinct_peers)
+	{ 
+		print fmt("orig: %s: peers: %s", o, distinct_peers[o]); 
+	} 
+
+}