diff --git a/examples/simple-alternate-routing.cc b/examples/simple-alternate-routing.cc
index c13bb3e89..acbd45270 100644
--- a/examples/simple-alternate-routing.cc
+++ b/examples/simple-alternate-routing.cc
@@ -54,32 +54,12 @@ main (int argc, char *argv[])
 #if 0 
   LogComponentEnable("GlobalRouteManager", LOG_LOGIC);
   LogComponentEnable("GlobalRouter", LOG_LOGIC);
-  LogComponentEnable("Object", LOG_LEVEL_ALL);
-  LogComponentEnable("Queue", LOG_LEVEL_ALL);
-  LogComponentEnable("DropTailQueue", LOG_LEVEL_ALL);
-  LogComponentEnable("Channel", LOG_LEVEL_ALL);
-  LogComponentEnable("CsmaChannel", LOG_LEVEL_ALL);
-  LogComponentEnable("NetDevice", LOG_LEVEL_ALL);
-  LogComponentEnable("CsmaNetDevice", LOG_LEVEL_ALL);
-  LogComponentEnable("Ipv4L3Protocol", LOG_LEVEL_ALL);
-  LogComponentEnable("PacketSocket", LOG_LEVEL_ALL);
-  LogComponentEnable("Socket", LOG_LEVEL_ALL);
-  LogComponentEnable("UdpSocket", LOG_LEVEL_ALL);
-  LogComponentEnable("UdpL4Protocol", LOG_LEVEL_ALL);
-  LogComponentEnable("Ipv4L3Protocol", LOG_LEVEL_ALL);
-  LogComponentEnable("Ipv4StaticRouting", LOG_LEVEL_ALL);
-  LogComponentEnable("Ipv4Interface", LOG_LEVEL_ALL);
-  LogComponentEnable("ArpIpv4Interface", LOG_LEVEL_ALL);
-  LogComponentEnable("Ipv4LoopbackInterface", LOG_LEVEL_ALL);
-  LogComponentEnable("OnOffApplication", LOG_LEVEL_ALL);
-  LogComponentEnable("PacketSinkApplication", LOG_LEVEL_ALL);
-  LogComponentEnable("UdpEchoClientApplication", LOG_LEVEL_ALL);
-  LogComponentEnable("UdpEchoServerApplication", LOG_LEVEL_ALL);
 #endif
-  // Set up some default values for the simulation.  Use the 
-  // DefaultValue::Bind () technique to tell the system what subclass of 
-  // Queue to use, and what the queue limit is
 
+  //
+  // Make the random number generators generate reproducible results.
+  //
+  RandomVariable::UseGlobalSeed (1, 1, 2, 3, 5, 8);
 
   Config::SetDefault ("ns3::OnOffApplication::PacketSize", Uinteger (210));
   Config::SetDefault ("ns3::OnOffApplication::DataRate", DataRate ("300b/s"));
diff --git a/examples/simple-error-model.cc b/examples/simple-error-model.cc
index acea35e77..381136353 100644
--- a/examples/simple-error-model.cc
+++ b/examples/simple-error-model.cc
@@ -58,6 +58,11 @@ main (int argc, char *argv[])
   LogComponentEnable ("SimplePointToPointExample", LOG_LEVEL_INFO);
 #endif
 
+  //
+  // Make the random number generators generate reproducible results.
+  //
+  RandomVariable::UseGlobalSeed (1, 1, 2, 3, 5, 8);
+
   // Set a few parameters
   Config::SetDefault ("ns3::RateErrorModel::ErrorRate", Double (0.01));
   Config::SetDefault ("ns3::RateErrorModel::ErrorUnit", String ("EU_PKT"));
diff --git a/examples/simple-global-routing.cc b/examples/simple-global-routing.cc
index 210492eb0..f6468f3bd 100644
--- a/examples/simple-global-routing.cc
+++ b/examples/simple-global-routing.cc
@@ -58,31 +58,14 @@ main (int argc, char *argv[])
   // for selected modules; the below lines suggest how to do this
 #if 0 
   LogComponentEnable ("SimpleGlobalRoutingExample", LOG_LEVEL_INFO);
-
-  LogComponentEnable("Object", LOG_LEVEL_ALL);
-  LogComponentEnable("Queue", LOG_LEVEL_ALL);
-  LogComponentEnable("DropTailQueue", LOG_LEVEL_ALL);
-  LogComponentEnable("Channel", LOG_LEVEL_ALL);
-  LogComponentEnable("CsmaChannel", LOG_LEVEL_ALL);
-  LogComponentEnable("NetDevice", LOG_LEVEL_ALL);
-  LogComponentEnable("CsmaNetDevice", LOG_LEVEL_ALL);
-  LogComponentEnable("Ipv4L3Protocol", LOG_LEVEL_ALL);
-  LogComponentEnable("PacketSocket", LOG_LEVEL_ALL);
-  LogComponentEnable("Socket", LOG_LEVEL_ALL);
-  LogComponentEnable("UdpSocket", LOG_LEVEL_ALL);
-  LogComponentEnable("UdpL4Protocol", LOG_LEVEL_ALL);
-  LogComponentEnable("Ipv4L3Protocol", LOG_LEVEL_ALL);
-  LogComponentEnable("Ipv4StaticRouting", LOG_LEVEL_ALL);
-  LogComponentEnable("Ipv4Interface", LOG_LEVEL_ALL);
-  LogComponentEnable("ArpIpv4Interface", LOG_LEVEL_ALL);
-  LogComponentEnable("Ipv4LoopbackInterface", LOG_LEVEL_ALL);
-  LogComponentEnable("OnOffApplication", LOG_LEVEL_ALL);
-  LogComponentEnable("PacketSinkApplication", LOG_LEVEL_ALL);
-  LogComponentEnable("UdpEchoClientApplication", LOG_LEVEL_ALL);
-  LogComponentEnable("UdpEchoServerApplication", LOG_LEVEL_ALL);
 #endif
-  // Set up some default values for the simulation.  Use the 
 
+  //
+  // Make the random number generators generate reproducible results.
+  //
+  RandomVariable::UseGlobalSeed (1, 1, 2, 3, 5, 8);
+
+  // Set up some default values for the simulation.  Use the 
   Config::SetDefault ("ns3::OnOffApplication::PacketSize", Uinteger (210));
   Config::SetDefault ("ns3::OnOffApplication::DataRate", DataRate ("448kb/s"));
 
diff --git a/regression/regression.py b/regression/regression.py
index 9932f0513..b339a0300 100644
--- a/regression/regression.py
+++ b/regression/regression.py
@@ -48,6 +48,8 @@ def main(tests = None, testdir = None):
     userName = "craigdo/"
     repoName = "ns-3-ref-traces/"
 
+    print "Synchronizing reference traces."
+    
     if not os.path.exists(repoName):
         cloneCmd = "hg clone http://code.nsnam.org/" + userName + repoName + " >& /dev/null"
         os.system(cloneCmd)
@@ -57,6 +59,8 @@ def main(tests = None, testdir = None):
         os.system(pullCmd)
         os.chdir("..")
 
+    print "Done."
+
     bad = []
 
     if not testdir:
diff --git a/regression/tests/test-simple-error-model.py b/regression/tests/test-simple-error-model.py
new file mode 100644
index 000000000..9b6b62ef0
--- /dev/null
+++ b/regression/tests/test-simple-error-model.py
@@ -0,0 +1,41 @@
+#! /usr/bin/env python
+
+"""Generic trace-comparison-type regression test."""
+
+import os
+import shutil
+
+def run(verbose, generate):
+    """Execute a test."""
+
+    testName = "simple-error-model"
+    repoName = "ns-3-ref-traces/"
+    refDirName = testName + ".ref"
+
+    if not os.path.exists(repoName):
+        print"No reference trace repository"
+        return 1
+
+    if generate:
+        if not os.path.exists(repoName + refDirName):
+            print "creating new " + repoName + refDirName
+            os.mkdir(repoName + refDirName)
+
+        os.system("./waf --cwd regression/" + repoName + refDirName +
+            " --run " + testName + " >& /dev/null")
+
+        print "Remember to commit " + repoName + refDirName
+        return 0
+    else:
+        if not os.path.exists(repoName + refDirName):
+            print "Cannot locate reference traces"
+            return 1
+
+        shutil.rmtree("traces");
+        os.mkdir("traces")
+        
+        os.system("./waf --cwd regression/traces --run " +
+          testName + " >& /dev/null")
+        
+        return os.system("diff -q traces " + repoName + refDirName +
+         " >& /dev/null")
diff --git a/regression/tests/test-simple-global-routing.py b/regression/tests/test-simple-global-routing.py
new file mode 100644
index 000000000..d47207866
--- /dev/null
+++ b/regression/tests/test-simple-global-routing.py
@@ -0,0 +1,41 @@
+#! /usr/bin/env python
+
+"""Generic trace-comparison-type regression test."""
+
+import os
+import shutil
+
+def run(verbose, generate):
+    """Execute a test."""
+
+    testName = "simple-global-routing"
+    repoName = "ns-3-ref-traces/"
+    refDirName = testName + ".ref"
+
+    if not os.path.exists(repoName):
+        print"No reference trace repository"
+        return 1
+
+    if generate:
+        if not os.path.exists(repoName + refDirName):
+            print "creating new " + repoName + refDirName
+            os.mkdir(repoName + refDirName)
+
+        os.system("./waf --cwd regression/" + repoName + refDirName +
+            " --run " + testName + " >& /dev/null")
+
+        print "Remember to commit " + repoName + refDirName
+        return 0
+    else:
+        if not os.path.exists(repoName + refDirName):
+            print "Cannot locate reference traces"
+            return 1
+
+        shutil.rmtree("traces");
+        os.mkdir("traces")
+        
+        os.system("./waf --cwd regression/traces --run " +
+          testName + " >& /dev/null")
+        
+        return os.system("diff -q traces " + repoName + refDirName +
+         " >& /dev/null")