getenv()

Hi folks, phpinfo() returns 2 tables of environment variables - one simply says environment variables, and the other says Apache environment. Both tables appear to have the CGI Specification variables set, but some of these values are set differently. I have an application that looks at the $REMOTE_USER environment variable to determine who is logged on, so we can display user specific information. Yes, this is not ideal, but we are unfortunately, using Kerberos to authenticate people into our intranet. Can anyone tell me, from which set of environment variables does getenv take it's values from? And why it is set differently? TIA, Ignatius