用 platform sdk + vc toolkit 编译 firefox 的错误

用 platform sdk + vc toolkit 编译 firefox 的错误

$ make -f client.mk build all
cd /cygdrive/d/mozilla/mozilla
/cygdrive/d/mozilla/mozilla/configure
Adding configure options from /cygdrive/d/mozilla/mozilla/.mozconfig:
--disable-accessibility
--disable-composer
--enable-debug
--disable-activex
--disable-installer
--disable-activex-scripting
--disable-ldap
--disable-calendar
--disable-mailnews
--disable-tests
--enable-crypto
--enable-extensions=cookie,xml-rpc,xmlextras,p3p,pref,transformiix,universalch
ardet,typeaheadfind,webservices,negotiateauth
loading cache ./config.cache
checking host system type... i686-pc-cygwin
checking target system type... i686-pc-cygwin
checking build system type... i686-pc-cygwin
checking for gcc... cl
checking whether the C compiler (cl ) works... yes
checking whether the C compiler (cl ) is a cross-compiler... no
checking whether we are using GNU C... no
checking whether cl accepts -g... no
checking for c++... cl
checking whether the C++ compiler (cl ) works... yes
checking whether the C++ compiler (cl ) is a cross-compiler... no
checking whether we are using GNU C++... no
checking whether cl accepts -g... no
checking for ranlib... ranlib
checking for ml... /cygdrive/c/Program Files/Microsoft Visual Studio .NET 2003/V
c7/bin/ml
checking for ar... ar
checking for ld... link
checking for strip... strip
checking for windres... windres
checking for midl... midl
configure: error: $(CXX) test failed. You must have MS VC++ in your path to bui
ld.
*** Fix above errors and then restart with "make -f client.mk build"
make: *** [/cygdrive/d/mozilla/mozilla/Makefile] Error 1


上面提示：

You must have MS VC++ in your path to build.

我已经在我的路径中加入了 相关路径，为什么还报这样的错误？