I see many people has this error, I had the same Problem

All you do is change

function getComments ($iCmtsParentId = null, &$iOverflow = null, &$iCountTotal = null)

to

function getComments ($iCmtsParentId = null, $iOverflow = null, $iCountTotal = null)

or

function getComments ($iCmtsParentId = 0, $iOverflow = 0, $iCountTotal = 0)

Enjoy