Postfix quota reject
Postfix quota reject is an open source project wich allows mail rejection at smtp time (with real time mailbox checks of quota status) when destination mailbox doesn't have enough space available for storing the incoming mail. This project is opened with BSD license and comes with ABSOLUTELY NO WARRANTY. All about the project, configuration, implementations and so... comes inside the tar.gz file downloadable here.
If you would like to suggest something, or something just doesn't work for you, or you have any kind of doubts... you could contact me by email but please enter on the subject of the mail "PQR" and the subject you want (for filtering easier). Send me an email.
I do paste here downladable tar.gz checksums :
md5 postfixquotareject20.tar.gz --> 64af49fe101a09c366e0d0a3f9757bbd
sha256 postfixquotareject20.tar.gz --> 2bf3c6a21081505a5c615c5994c913c2b8aa01dfdfd83b6ef3c3d5abc4f4e166