Description:
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When I'm using the imap_header() function to parse an email account emails very often the script is crashing with "Segmentation fault".
I saw this in the PHP bugs, but they all was old and for the oldest PHP versions. Now I have this bug again.

Reproduce code:
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$mailbox=imap_open("{mail.myhost.com:110/pop3}INBOX","support","****");
$check = imap_check($mailbox);
$messages=$check->Nmsgs;
for($i=1;$i<=$messages;$i++)
{
    $header = imap_headerinfo($mailbox,$i);
    print_r($header);
    echo date("Y-m-d",$header->udate)."\n";
}

Expected result:
----------------
I expect to see the dates of the all emails.

Actual result:
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When I execute the code it began to parse the emails. After few emails the script hangs for round a minute (or less) and then I receive the last print_r() results and then Segmentation fault.
The above URL is what the print_r() returns.
http://www.toshko-bg.com/toto/bad_email.html