diff --git a/doc/src/sgml/install-windows.sgml b/doc/src/sgml/install-windows.sgml
index 8cd189c8e15..50116f315dc 100644
--- a/doc/src/sgml/install-windows.sgml
+++ b/doc/src/sgml/install-windows.sgml
@@ -145,6 +145,14 @@ $ENV{PATH}=$ENV{PATH} . ';c:\some\where\bison\bin';
 </programlisting>
  </para>
 
+ <para>
+  To pass additional command line arguments to the Visual Studio build
+  command (msbuild or vcbuild):
+<programlisting>
+$ENV{MSBFLAGS}="/m";
+</programlisting>
+ </para>
+
  <sect2>
   <title>Requirements</title>
   <para>
diff --git a/src/tools/msvc/build.pl b/src/tools/msvc/build.pl
index 007e3c73b25..52739774c79 100644
--- a/src/tools/msvc/build.pl
+++ b/src/tools/msvc/build.pl
@@ -38,6 +38,7 @@ my $vcver = Mkvcbuild::mkvcbuild($config);
 # check what sort of build we are doing
 
 my $bconf     = $ENV{CONFIG} || "Release";
+my $msbflags  = $ENV{MSBFLAGS} || "";
 my $buildwhat = $ARGV[1]     || "";
 if (uc($ARGV[0]) eq 'DEBUG')
 {
@@ -53,16 +54,16 @@ elsif (uc($ARGV[0]) ne "RELEASE")
 if ($buildwhat and $vcver >= 10.00)
 {
 	system(
-		"msbuild $buildwhat.vcxproj /verbosity:normal /p:Configuration=$bconf"
+		"msbuild $buildwhat.vcxproj $msbflags /verbosity:normal /p:Configuration=$bconf"
 	);
 }
 elsif ($buildwhat)
 {
-	system("vcbuild $buildwhat.vcproj $bconf");
+	system("vcbuild $msbflags $buildwhat.vcproj $bconf");
 }
 else
 {
-	system("msbuild pgsql.sln /verbosity:normal /p:Configuration=$bconf");
+	system("msbuild pgsql.sln $msbflags /verbosity:normal /p:Configuration=$bconf");
 }
 
 # report status
diff --git a/src/tools/msvc/clean.bat b/src/tools/msvc/clean.bat
index 469b8a24b29..e21e37f6f76 100755
--- a/src/tools/msvc/clean.bat
+++ b/src/tools/msvc/clean.bat
@@ -107,6 +107,6 @@ REM for /r %%f in (*.sql) do if exist %%f.in del %%f
 cd %D%
 
 REM Clean up ecpg regression test files
-msbuild /NoLogo ecpg_regression.proj /t:clean /v:q
+msbuild %MSBFLAGS% /NoLogo ecpg_regression.proj /t:clean /v:q
 
 goto :eof
diff --git a/src/tools/msvc/vcregress.pl b/src/tools/msvc/vcregress.pl
index b4f946474f5..bcf22677acd 100644
--- a/src/tools/msvc/vcregress.pl
+++ b/src/tools/msvc/vcregress.pl
@@ -138,8 +138,9 @@ sub check
 
 sub ecpgcheck
 {
+	my $msbflags  = $ENV{MSBFLAGS} || "";
 	chdir $startdir;
-	system("msbuild ecpg_regression.proj /p:config=$Config");
+	system("msbuild ecpg_regression.proj $msbflags /p:config=$Config");
 	my $status = $? >> 8;
 	exit $status if $status;
 	InstallTemp();