Hi,
I am the lead programmer of the POP3 based webmail application called Postaci. It is able to fetch attachments. You can test it at http://webmail.onar.com.tr with the username & password : misafir
You can download it from ftp://ftp.onar.com.tr/pub/linux/postaci
Well I was also searching for a way to fetch mails and decode MIME. I can say that it is possible but too much effort is needed. PHP provides IMAP/POP3/NNTP functions if it is compiled with the c-client libraries and they are so powerful that I couldn' t avoid using them.
Don' t need to reinvent the whell, simply use them 🙂
Regards
Umut Gokbayrak