This one looks a lot like the Netscape.py bouncer is already set up to handle, but the bouncing address is not where Netscape expects it (Postmaster@mail.hypercon.com is there instead).
Not quite sure how to handle this sort of bounce; would it be better to look for "The following recipients..." just in general rather than "Please reply to"?
This Message was undeliverable due to the following reason:
The recipient(s) indicated below did not receive this message because their mailbox size limit would have been exceeded. It has been returned and it is recommended that you contact the recipient and request that space be made available within their mailbox.
Note: The Postmaster for this mail server may increase the mailbox quota on the account referenced below to accommodate the delivery of additional mail.
No storage space available in mailbox for firstname.lastname@example.org
The following recipients haven't received this message:
Please reply to Postmaster@mail.hypercon.com if you feel this message to be in error.