bigpond message content rejected due to suspected spam ib704x

hi all,

i am unable to send emails to a colleague who has a bigpond address. initially i was able to, but now every time i try i fail. what is most interesting is the "mail delivery system" emails i receive entitled "undelivered mail returned to sender" go into my junk box and not my inbox. so initially i was never aware my emails were bouncing.

i know the problem is at the bigpond end but wondering if anyone has had a smilier issue.

most suggestions online involve emailing postmaster@bigpond.com about the problem, but i get the same problem - returned mail. so something about my email address has been connected to spam and bigpond has now tagged it as such.