diff --git a/bin/tests/system/Makefile.in b/bin/tests/system/Makefile.in
index 1b7ff31dd7..cfd8e16d24 100644
--- a/bin/tests/system/Makefile.in
+++ b/bin/tests/system/Makefile.in
@@ -92,7 +92,7 @@ parallel.mk:
 	for directory in $(PARALLEL) ; do \
 		echo "" >> $@ ; \
 		echo "test-`echo $$directory | tr _ -`:" >> $@ ; \
-		echo "	@$(SHELL) ./run.sh $$NOCLEAN -r -p $$port $$directory 2>&1 | tee $$directory/test.output" >> $@ ; \
+		echo "	@$(SHELL) ./run.sh -r -p $$port $$directory 2>&1 | tee $$directory/test.output" >> $@ ; \
 		port=`expr $$port + 100` ; \
 	done
 
@@ -100,7 +100,7 @@ parallel.mk:
 
 test: parallel.mk subdirs
 	@$(MAKE) -f parallel.mk check
-	@$(SHELL) ./runsequential.sh $$NOCLEAN -r
+	@$(SHELL) ./runsequential.sh -r
 	@$(SHELL) ./testsummary.sh
 
 check: test
diff --git a/bin/tests/system/README b/bin/tests/system/README
index 4bf6719d44..81cca41605 100644
--- a/bin/tests/system/README
+++ b/bin/tests/system/README
@@ -129,7 +129,10 @@ Running All The System Tests
 ---
 To run all the system tests, enter the command:
 
-    sh runall.sh [-n] [numproc]
+    sh runall.sh [-c] [-n] [numproc]
+
+The optional flag "-c" forces colored output (by default system test output is
+not printed in color due to run.sh being piped through "tee").
 
 The optional flag "-n" has the same effect as it does for "run.sh" - it causes
 the retention of all output files from all tests.
@@ -153,11 +156,13 @@ A run of all the system tests can also be initiated via make:
     make [-j numproc] test
 
 In this case, retention of the output files after a test completes successfully
-is specified by setting the environment variable NOCLEAN to "-n" prior to
-running make, e.g.
+is specified by setting the environment variable SYSTEMTEST_NO_CLEAN to 1 prior
+to running make, e.g.
 
-    NOCLEAN=-n make [-j numproc] test
+    SYSTEMTEST_NO_CLEAN=1 make [-j numproc] test
 
+while setting environment variable SYSTEMTEST_FORCE_COLOR to 1 forces system
+test output to be printed in color.
 
 
 Running Multiple System Test Suites Simultaneously
@@ -714,7 +719,7 @@ the ports are assigned when the tests are run.  This is achieved by having the
 when "make check" is run, and contains a target for each test of the form:
 
     <test-name>:
-        @$(SHELL) run.sh $$NOCLEAN -r -p <baseport> <test-name>
+        @$(SHELL) run.sh -r -p <baseport> <test-name>
 
 The <baseport> is unique and the values of <baseport> for each test are
 separated by at least 100 ports.
diff --git a/bin/tests/system/conf.sh.in b/bin/tests/system/conf.sh.in
index 62323ffd4b..95a5d332a1 100644
--- a/bin/tests/system/conf.sh.in
+++ b/bin/tests/system/conf.sh.in
@@ -166,7 +166,7 @@ NZD=@NZD_TOOLS@
 #
 # Set up color-coded test output
 #
-if test -t 1 && type tput > /dev/null 2>&1 ; then
+if [ ${SYSTEMTEST_FORCE_COLOR:-0} -eq 1 ] || test -t 1 && type tput > /dev/null 2>&1 ; then
     COLOR_END=`tput setaf 4`    # blue
     COLOR_FAIL=`tput setaf 1`   # red
     COLOR_INFO=`tput bold`      # bold
diff --git a/bin/tests/system/run.sh b/bin/tests/system/run.sh
index 60e6395da7..9abdedbba8 100644
--- a/bin/tests/system/run.sh
+++ b/bin/tests/system/run.sh
@@ -17,9 +17,14 @@ SYSTEMTESTTOP=.
 . $SYSTEMTESTTOP/conf.sh
 
 stopservers=true
-clean=true
 baseport=5300
 
+if [ ${SYSTEMTEST_NO_CLEAN:-0} -eq 1 ]; then
+	clean=false
+else
+	clean=true
+fi
+
 while getopts "knp:r" flag; do
     case "$flag" in
 	k) stopservers=false ;;
diff --git a/bin/tests/system/runall.sh b/bin/tests/system/runall.sh
index 5aa9412454..c0e714d614 100644
--- a/bin/tests/system/runall.sh
+++ b/bin/tests/system/runall.sh
@@ -12,7 +12,9 @@
 # Run all the system tests.
 #
 # Usage:
-#    runall.sh [-n] [numprocesses]
+#    runall.sh [-c] [-n] [numprocesses]
+#
+#   -c          Force colored output.
 #
 #   -n          Noclean.  Keep all output files produced by all tests.  These
 #               can later be removed by running "cleanall.sh".
@@ -25,14 +27,19 @@
 SYSTEMTESTTOP=.
 . $SYSTEMTESTTOP/conf.sh
 
-usage="Usage: ./runall.sh [-n] [numprocesses]"
+usage="Usage: ./runall.sh [-c] [-n] [numprocesses]"
 
-# Handle "-n" switch if present.
+# Preserve values of environment variables which are already set.
 
-NOCLEAN=""
-while getopts "n" flag; do
+SYSTEMTEST_FORCE_COLOR=${SYSTEMTEST_FORCE_COLOR:-0}
+SYSTEMTEST_NO_CLEAN=${SYSTEMTEST_NO_CLEAN:-0}
+
+# Handle command line switches if present.
+
+while getopts "cn" flag; do
     case "$flag" in
-        n) NOCLEAN="-n" ;;
+        c) SYSTEMTEST_FORCE_COLOR=1 ;;
+        n) SYSTEMTEST_NO_CLEAN=1 ;;
     esac
 done
 export NOCLEAN
@@ -57,6 +64,9 @@ fi
 
 # Run the tests.
 
+export SYSTEMTEST_FORCE_COLOR
+export SYSTEMTEST_NO_CLEAN
+
 status=0
 if [ "$CYGWIN" = "" ]; then
     # Running on Unix, use "make" to run tests in parallel.
@@ -69,7 +79,7 @@ else
     # used, the tests would be run sequentially anyway.)
     {
         for testdir in $SUBDIRS; do
-            $SHELL run.sh $NOCLEAN $testdir || status=1
+            $SHELL run.sh $testdir || status=1
         done
     } 2>&1 | tee "systests.output"
 fi