(PHP 3>= 3.0.15, PHP 4 , PHP 5)
imap_utf7_encode -- Converts ISO-8859-1 string to modified UTF-7 text.Converts data to modified UTF-7 text. Note that data is expected to be encoded in ISO-8859-1.
This is needed to encode mailbox names that contain certain characters which are not in range of printable ASCII characters.
The modified UTF-7 encoding is defined in RFC 2060, section 5.1.3 (original UTF-7 was defined in RFC1642).
See also: imap_utf7_decode().