Whoops! To *really* simulate the RefererIgnore directive, you also need to drop blank http_referer fields. So make that:
SetEnvIf Referer "^http://www\.mydomain\.com|www\.mydomain\.com|^$" intra_site_referral
Whoops! To *really* simulate the RefererIgnore directive, you also need to drop blank http_referer fields. So make that:
SetEnvIf Referer "^http://www\.mydomain\.com|www\.mydomain\.com|^$" intra_site_referral