patch for mozilla thunderbird requested

in the feature request to add hashcash in mozilla thunderbird,

https://bugzilla.mozilla.org/show_bug.cgi?id=229686

which currently has status "WONTFIX", after i countered the arguments that 
caused it to get that status, the following happened:

i gave argument:

"this request is not about adding the 16 MB library, but about adding 
hashcash, which is simple and can be implemented in little size."

Ludovic Hirlimann then posted:

"Please provide a patch so we can figure out how much this would add and 
then decide if we want it in the product or not."

i'm asking hereby if someone can produce a patch to add hashcash to 
thunderbird, and post on there.