There's nothing around on this, MS don't seem to have documented much at all about it...any code examples or explanations of how this can be used would be appreciated.
It's part of the Microsoft.Crm.Sdk.Query namespace.
Dear,
see articles you will get it.
http://kbalertz.com/930464/fields-available-search-criteria-Advanced-Microsoft-Dynamics.aspx
http://support.microsoft.com/kb/930464/zh-cn
Regards,
Imran
http://microsoftcrm3.blogspot.com