"spl" module is OK if compiling into PHP, but not as external module

["John N" <johnn3098@xxxxxxxxx>]

Hello,

I've built Php5 with "--with-spl" correctly.  There are no errors that I see.

Now, I'm trying to build & install module "spl.so" separately from Php.

As is usual, I execute

  php-src/etc/spl
  phpize
  ./configure
  make install

But, now 'make' display the error,

 ...
 config.status: config.h is unchanged
 Installing shared extensions:
/usr/local/lib/php/extensions/no-debug-zts-20060613/
 cp: target `/usr/local/lib/php/extensions/no-debug-zts-20060613/#INST@1466#'
is not a directory
 make: *** [install-modules] Error 1

Exploring in 'Makefile', I see the

 install-modules: build-modules
     @test -d modules && \
     $(mkinstalldirs) $(INSTALL_ROOT)$(EXTENSION_DIR)
     @echo "Installing shared extensions:     $(INSTALL_ROOT)$(EXTENSION_DIR)/"
     @rm -f modules/*.la >/dev/null 2>&1
     @$(INSTALL) modules/* $(INSTALL_ROOT)$(EXTENSION_DIR)

And,

 build-modules: $(PHP_MODULES)

 libphp$(PHP_MAJOR_VERSION).la: $(PHP_GLOBAL_OBJS) $(PHP_SAPI_OBJS)
         $(LIBTOOL) --mode=link $(CC) $(CFLAGS) $(EXTRA_CFLAGS) -rpath
$(phptempdir) $(EXTRA_LDFLAGS) $(LDFLAGS) $(PHP_RPATHS)
$(PHP_GLOBAL_OBJS) $(PHP_SAPI_OBJS) $(EXTRA_LIBS) $(ZEND_EXTRA_LIBS)
-o $@
         -@$(LIBTOOL) --silent --mode=install cp $@ $(phptempdir)/$@
>/dev/null 2>&1

Where, I think, the problem is with,

 --mode=install cp $@ $(phptempdir)/$@

in the last line I've included.

I'm not certain why this is OK when building "--with-spl" into Php,
but not standing alone.

Can someone, perhaps, see & explain the problem?

Thanks.

John