well it could be that the bt server had it stuck in its mailq for a day or so, or it could be that the ntl mailserver was not responding to requests on port 25... or maybe the bt mailserver was on a blacklist...
there are ohhh so many possibilities of what happens
and we are blind without looking at mail logs
but we both know that no major isp will give you details of what is in it's mailq and what happened in its maillogs, ntl wouldnt and neither would bt
