URL API p.php?AT=LI failing for host login with BadWebExIDOrPassword

We are using the following supported URL API for partner login to host a session  for one of our customer sites:

https://sitename/wbg/p.php?AT=LI&WID=username&PW=password

This method has been working successfully for our integration point for over 2 years.  Since October 12th we started receiving the following error:    &RS=BadWebExIDOrPassword

The account name and password are valid - we can login directly to Webex without issue

We get the same error regardless of whether we use HTTP GET or HTTP POST

We use the same integration point with several other customers using different hosted WebEx environments without issue

XML API version for the environment with the issue is 8.0

Any assistance would be appreciated as have no idea why this would suddenly stop working unless the WebEx hosted platform had been upgraded.  We have been informed that it is in 'lockdown' mode and has not been changed.

Thanks

Ian

This issue was addressed via email. The answer to the question is:

The URL API no longer supports using GET methods, only POST. One way to tell what is being used is to check the URL you are using to make the API call. Any URL that includes its variables in the URL string, such as:

https://sitename/wbg/p.php?AT=LI&WID=username&PW=password

is using the GET method.

Communication about POST requirement was first sent mid 2014 to developers, this remains visible on the developer community page, http://www.webexdeveloper.com under the security notices on the main page for June 2014

Direct links:

API Enhancements

https://support.webex.com/LocalizedUpgrades/WBS29-7/Security_Enforcement_Developer_Notification.pdf

API FAQ
https://support.webex.com/LocalizedUpgrades/WBS29-7/WebEx_Security_API_FAQ1.pdf

This feature should still be configurable at this time (November 2015), but is planned to be enforced by the end of the year.