X.509 Certs through SAP .NET Connector

Has anyone successfully passed an X.509 certificate through the SAP .NET Connector?

I am seeing a variety of errors based on information passed, but I am not seeing any type of success or descriptive error. Some of the error messages include

"No entries were deleted"

"Table is currently locked"

"Connection closed with no message"

I am using the SAP .NET Connector documentation as a guide and searching SAP Notes for any information. Are there any additional sources of documentation?

Some specific questions:

Can SSO with X.509 be used on a Windows XP development environment? (saw some documentation that only mentioned Windows2000)

Can the ASPNET_WP run as the default system account (LOCALHOST\ASPNET)? Does ASPNET_WP need to run as a domain account for configuration in SNC0?

Is there a specific SNC_Lib dll necessary for passing X.509 certificates?

thanks,

dave