The fix has been implemented and has stopped the outgoing spam e-mails.
There for this incident has been resolved.
For further details see our blog:
http://blog.e-conomic.dk/falske-e-mails-fra-e-conomic-i-omlob/

A fix has been implemented and we are monitoring the results.
Some emails might still be flagged as spam, while we wait for our spam score to improve again.

We are currently investigating our email sending IPs being blacklisted by some spam blacklist providers. We are investigating why.