mail headers & filtering

I sent this mail earlier:- "More and more emails seem to be getting blocked by mail filtering systems looking for spam (but trashing legitimate mail at the same time). Does anyone have any tips for ensuring mails get through these systems (with regard to headers) or do we just have to accept now that email can no longer be relied upon as a means of communication?" I don't know if it arrived or if there were any replies due to my own provider blocking my mails - I know they are doing it because I tested it myself and because I have just subscribed to this list under another email address - this other email ad is receiving the php list mails the other is not. Time to change ISP but anyway, if this mail was received and there were any replies, I'd be grateful if someone could forward them to me. Thanks Debbie