Mailhandler not importing all messages

is there anything in the watchdog? might be an PHP IMAP problem

See also 104249. There is a log message generated, but nobody knows what it's complaining about.

Doh. 98723.

same problem here. mailhandler for some reason ignores some messages. i did some debugging and found out that mailhandler sees these messages but it treats them as empty and so refuses to download them. i have no idea why - messages are correct and they display in a webmail client ad download with thunderbird without a problem... but mailhandler treats them as empty. any ideas?

ok, upon further testing i've found out that the problem (at least in my case) lies in this line

function mailhandler_get_part($stream, $msg_number, $mime_type, $structure = false, $part_number = false) {
  ...
  $text = imap_fetchbody($stream, $msg_number, $part_number);
  ...
  return drupal_convert_to_utf8($text, $encoding);
  ...

it looks like function drupal_convert_to_utf8 is unable to handle correctly the message body (returned earlier by imap_fetchbody function) and it returns an empty string. this empty string travels back to mailhandler_retrieve function which treats our message as empty.
unfortunately my knowledge ends here :( i have no idea why function drupal_convert_to_utf8 fails and how to prevent that. someone more skilled than me should take look at this code.
i did some more testing that may be of some help to others: the message body that breaks the whole process probably contains some wrongly encoded characters, because when i omit call to drupal_convert_to_utf8 and just return unconverted body i get only part of it that ends just before first non ASCII char. what's wired all the message headers looks fine. It is hard for me to debug this closely because the content that gets cut is generated by a mail server when message goes through it.
to me it looks like the mail server encoding is different that message encoding itself. the mail server just ignores the message encoding and injects its content using different encoding what possibly may cause trouble.
off course the mail itself is displayed with the whole body in place when i view my mailbox with through my web browser, but encoding is clearly broken - the non ASCII char that gets cut from the body in mailhandler module is displayed incorrectly, but still it is there and all that's after it.

In my case the problem was iconv, GNU recode and mbstring disabled on my shared host.

Unsupported encoding 'UTF-8'. Please install iconv, GNU recode or mbstring for PHP."