win7中的 安装xampp-win32-1.8.1-VC9 在php.ini中打开php_p...

win7中的 安装xampp-win32-1.8.1-VC9 在php.ini中打开php_pg_sql.dll之后提示
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httpd.exe - 系统错误
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无法启动此程序，因为计算机中丢失 LIBPQ.dll。尝试重新安装该程序以解决此问题。 
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确定   
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解决方法是：将LIBPQ.dll拷贝到 apache/bin目录中即可。
When start the apache right after you installed apache and php, you may got 无法启动此程序，因为计算机中丢失LIBPQ.DLL。尝试重新安装该程序以解决此问题。 error message, and apache doesn't work anymore.
I found LIBPQ.DLL were in the PHP_HOME, and think the php5apache2_2.dll which mentioned in httpd.conf file may reference it. but it is not in the apache home, so 
I copied LIBPQ.DLL into the apache bin folder, then it works. and the better idea may be put it in to the PATH environment variable..