Symptom: 

• You receive the following error with a PHP script: "Bad Gateway.  Web server received an invalid response while acting as a gateway or proxy server."
• Your hosting server is running version 4.4.2 of PHP 4 (place a phpinfo page on your site to check the version of php, or contact the support team to ask what version is runing in your hosting space)

Possible Resolution:

• This error can be generated by PHP for several reasons, but we have identified that PHP 4.4.2 can generate this error due to a bug in this version.  If you're experiencing these symptoms, please contact support who can review the scenario and upgrade PHP 4 version to 4.4.7.