WITH the saintly Mother Teresa recuperating from a recent fall in which she broke her ribs, she needs plenty of cheering up. So, in Dublin's fair city, that's what Hongkong police inspector Gerard Tannam will attempt to do today when he comes face-to-face with the Nobel Peace Prize winner, who is visiting the Irish capital. Irishman Gerard's mum put him up to it, sending the Lord Mayor of Dublin a copy of the words of a song Indian Sun , which her son wrote as a tribute to Mother Teresa's work among the poor of the Indian sub-continent. As a result, Gerard, who timed his visit to see the folks back home well, has been invited by the mayor to serenade the famous nun with his song. Gerard, we are sure, will rise commendably to the challenge, given he is a founding member of local groups The Shadowboxers and The Wild Geese - in both of which he excelled as lead singer. There is more than just music and poetry, it seems, to the man. We are told he's also an art consultant and is soon to put on some exhibitions through his own company, Arts 'N Noise. But back to today's important musical appointment. ''It's a typical Irish tale of a mother pushing her son,'' he bashfully says. Mother T would, no doubt, give her blessings to that.