mod_php environment

How do I configure which variables are passed to mod_php's environment? I'm working on a project using Jon Praise' superb PHP SASL bindings - http://cgi.sfu.ca/~jdbates/moin/moin.cgi/SquirrelMail&SASL Using GSSAPI authentication requires a KRB5CCNAME environment variable be passed from mod_auth_kerb to the SASL C library It works great with php-cgi - the PHP environment contains all the variables from the Apache environment - but with mod_php, the PHP environment contains only LANG & PATH I can still get the value of KRB5CCNAME using $_SERVER['KRB5CCNAME'], but because $_ENV['KRB5CCNAME'] doesn't work, GSSAPI authentication fails Because SquirrelMail - & even the PHP SASL bindings - are designed to be abstract from any one particular authentication mechanism, I don't think the PHP script is the right place for $_ENV['KRB5CCNAME'] = $_SERVER['KRB5CCNAME'] Instead, I want to configure mod_php to pass KRB5CCNAME from Apache's environment to the PHP environment - but so far no luck figuring out how Help much appreciated! Thanks! Jack