"If you are an authoritative administrator of t.co and you have solved the abuse issues you can write to us at dbl-mmxi@spamhaus.org from either abuse@t.co or postmaster@t.co and inform us of the actions you have taken to clean up the current spammer URLs. Please also inform us of any steps you have taken to prevent future abuse of your shortener/redirector. We will review your request and, at our discretion, remove the listing or respond to your request."
Funny recommendation there:
"If you are an authoritative administrator of t.co and you have solved the abuse issues you can write to us at dbl-mmxi@spamhaus.org from either abuse@t.co or postmaster@t.co and inform us of the actions you have taken to clean up the current spammer URLs. Please also inform us of any steps you have taken to prevent future abuse of your shortener/redirector. We will review your request and, at our discretion, remove the listing or respond to your request."
:)