Description:
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We need to have the ability to use kerberos authentication with the SOAP extension. At the moment, the SOAP extension only provides BASIC and DIGEST authentication.

Environment:
Client
Windows XP/Vista/7
IE 7/8

Webserver
Windows 2003/2008 Server
IIS 7
ZendServer PHP 5.2.11

Exchange Server
Windows 2003/2008
Exchange WS 2007/2010

Scenario:
client  -- request (kerberos auth) -->  webserver  -- SOAP request (client kerberos auth) -->  Exchange WS

The SOAP request doesn't forward the client kerberos token, so we can't authenticate on the exchange server.

We also tried to override the __doRequest function and reproduce the whole procedure with the cURL extension. We then could authenticate with NTLM, but we couldn't find any cURL binaries with GSSAPI support neither could we compile cURL with GSSAPI support on windows - so GSSNEGOTIATE authentication could not be set as cURL-option --> we couldn't test that yet and we won't be able to without any help.