Just a quick note that may be helpful for some:
It seems to me that this function also modifies the HTTP Content-Type header that's sent to the client (at least in combination with the iconv_set_encoding() function).
If you specify an encoding ending with "//TRANSLIT" or "//IGNORE" (valid in iconv), it will still send the encoding name in the HTTP header. This makes it an invalid character set unfortunately.
For example:
<?php
iconv_set_encoding("internal_encoding","UTF-8");
iconv_set_encoding("output_encoding","ISO-8859-1//TRANSLIT");
ob_start("ob_iconv_handler");
?>
will send a Content-Type header of "ISO-8859-1//TRANSLIT".
iconv