diff --git a/src/tools/msvc/Mkvcbuild.pm b/src/tools/msvc/Mkvcbuild.pm
index c71ea446bc..469563e4a9 100644
--- a/src/tools/msvc/Mkvcbuild.pm
+++ b/src/tools/msvc/Mkvcbuild.pm
@@ -3,7 +3,7 @@ package Mkvcbuild;
 #
 # Package that generates build files for msvc build
 #
-# $PostgreSQL: pgsql/src/tools/msvc/Mkvcbuild.pm,v 1.12 2007/06/12 11:07:34 mha Exp $
+# $PostgreSQL: pgsql/src/tools/msvc/Mkvcbuild.pm,v 1.13 2007/06/12 18:31:28 mha Exp $
 #
 use Carp;
 use Win32;
@@ -148,6 +148,7 @@ sub mkvcbuild
     my $ecpg = $solution->AddProject('ecpg','exe','interfaces','src\interfaces\ecpg\preproc');
     $ecpg->AddIncludeDir('src\interfaces\ecpg\include');
     $ecpg->AddIncludeDir('src\interfaces\libpq');
+    $ecpg->AddPrefixInclude('src\interfaces\ecpg\preproc');
     $ecpg->AddFiles('src\interfaces\ecpg\preproc','pgc.l','preproc.y');
     $ecpg->AddDefine('MAJOR_VERSION=4');
     $ecpg->AddDefine('MINOR_VERSION=2');
diff --git a/src/tools/msvc/Project.pm b/src/tools/msvc/Project.pm
index f35580bfac..1c83df6d2a 100644
--- a/src/tools/msvc/Project.pm
+++ b/src/tools/msvc/Project.pm
@@ -3,7 +3,7 @@ package Project;
 #
 # Package that encapsulates a Visual C++ project file generation
 #
-# $PostgreSQL: pgsql/src/tools/msvc/Project.pm,v 1.11 2007/03/29 15:30:52 mha Exp $
+# $PostgreSQL: pgsql/src/tools/msvc/Project.pm,v 1.12 2007/06/12 18:31:28 mha Exp $
 #
 use Carp;
 use strict;
@@ -27,6 +27,7 @@ sub new
         libraries       => [],
         suffixlib       => [],
         includes        => '',
+        prefixincludes  => '',
         defines         => ';',
         solution        => $solution,
         disablewarnings => '4018;4244;4273;4102',
@@ -128,6 +129,13 @@ sub AddIncludeDir
     $self->{includes} .= $inc;
 }
 
+sub AddPrefixInclude
+{
+    my ($self, $inc) = @_;
+
+    $self->{prefixincludes} = $inc . ';' . $self->{prefixincludes};
+}
+
 sub AddDefine
 {
     my ($self, $def) = @_;
@@ -467,7 +475,7 @@ sub WriteConfiguration
   <Configuration Name="$cfgname|Win32" OutputDirectory=".\\$cfgname\\$self->{name}" IntermediateDirectory=".\\$cfgname\\$self->{name}"
 	ConfigurationType="$cfgtype" UseOfMFC="0" ATLMinimizesCRunTimeLibraryUsage="FALSE" CharacterSet="2" WholeProgramOptimization="$p->{wholeopt}">
 	<Tool Name="VCCLCompilerTool" Optimization="$p->{opt}"
-		AdditionalIncludeDirectories="src/include;src/include/port/win32;src/include/port/win32_msvc;$self->{includes}"
+		AdditionalIncludeDirectories="$self->{prefixincludes}src/include;src/include/port/win32;src/include/port/win32_msvc;$self->{includes}"
 		PreprocessorDefinitions="WIN32;_WINDOWS;__WINDOWS__;__WIN32__;EXEC_BACKEND;WIN32_STACK_RLIMIT=4194304;_CRT_SECURE_NO_DEPRECATE;_CRT_NONSTDC_NO_DEPRECATE$self->{defines}$p->{defs}"
 		StringPooling="$p->{strpool}"
 		RuntimeLibrary="$p->{runtime}" DisableSpecificWarnings="$self->{disablewarnings}"