diff --git a/src/iosource/Manager.cc b/src/iosource/Manager.cc
index 00fc61ff5c..57f3caecdf 100644
--- a/src/iosource/Manager.cc
+++ b/src/iosource/Manager.cc
@@ -136,6 +136,8 @@ void Manager::FindReadySources(std::vector<IOSource*>* ready)
 		if ( iosource->IsOpen() )
 			{
 			double next = iosource->GetNextTimeout();
+			bool added = false;
+
 			if ( timeout == -1 || ( next >= 0.0 && next < timeout ) )
 				{
 				timeout = next;
@@ -146,13 +148,29 @@ void Manager::FindReadySources(std::vector<IOSource*>* ready)
 				// we don't want things in the vector passed into Poll() or it'll end
 				// up inserting duplicates.
 				if ( timeout == 0 && ! time_to_poll )
+					{
+					added = true;
 					ready->push_back(timeout_src);
+					}
 				}
 
-			// Avoid calling Poll() if we can help it since on very high-traffic
-			// networks, we spend too much time in Poll() and end up dropping packets.
-			if ( ! time_to_poll && iosource == pkt_src && pkt_src->IsLive() )
-				ready->push_back(pkt_src);
+			if ( iosource == pkt_src && ! added )
+				{
+				if ( pkt_src->IsLive() )
+					{
+					if ( ! time_to_poll )
+						// Avoid calling Poll() if we can help it since on very
+						// high-traffic networks, we spend too much time in
+						// Poll() and end up dropping packets.
+						ready->push_back(pkt_src);
+					}
+				else
+					{
+					if ( ! pseudo_realtime )
+						// A pcap file is always ready to process.
+						ready->push_back(pkt_src);
+					}
+				}
 			}
 		}
 
diff --git a/testing/btest/Baseline/core.network-time-init/out b/testing/btest/Baseline/core.network-time-init/out
new file mode 100644
index 0000000000..0324e77fa6
--- /dev/null
+++ b/testing/btest/Baseline/core.network-time-init/out
@@ -0,0 +1,2 @@
+0.0
+1362692526.869344
diff --git a/testing/btest/core/network-time-init.zeek b/testing/btest/core/network-time-init.zeek
new file mode 100644
index 0000000000..cea9b3f85f
--- /dev/null
+++ b/testing/btest/core/network-time-init.zeek
@@ -0,0 +1,15 @@
+# @TEST-EXEC: zeek -b -r $TRACES/http/get.trace %INPUT >out
+# @TEST-EXEC: btest-diff out
+
+event my_init()
+	{
+	# Expect time to be initialized (PktSrc was processed at least once).
+	print network_time();
+	}
+
+event zeek_init()
+	{
+	# Expect time to be zero
+	print network_time();
+	schedule 0sec { my_init() };
+	}