imap and multipart

hello, i work with imap and php to make a webmail. it works fine but i have a big problem with some mails, those who contains a multipart into a multipart. it happends with outlook express who puts into a mutlipart the text and html version of the text into the first part of the mail. an other case is when i forward a mail, the whole mail is fully contained into a part of the mail. the problem is that with the imap commands i cannot access into these parts to retrieve their contents. if someone could help me ! thx --maxime--