The news of the 25-year-old's inclusion has tempered the withdrawal of Ireland captain Brian O'Driscoll - due to skipper the 'North' against a Rod Macqueen-coached 'South' - although the Leinster centre will be present at pitchside.
With O'Driscoll sidelined as a precaution due to ''minor injuries sustained against England last Sunday'', North coach Sir Clive Woodward said: "I have spoken to Brian and he is bitterly disappointed not to be playing. However, he has come over for the game to show his support from the guys.
"I am delighted that Lawrence (Dallaglio) is involved as captain. He is a proven, outstanding player and he is relishing the prospect of stepping up to the mark and taking on the role of captaincy for this unique match."
Ireland boast three players in Woodward's playing squad, with O'Callaghan being joined by Ulster fly-half and North vice-captain David Humphreys, who partners Wales' Gareth Cooper at half-back, and Leinster back row Eric Miller - a late call-up to replace France's Olivier Brouzet on the replacements bench.
Humphreys' battle with opposite number Andrew Mehrtens of New Zealand should be an intriguing one.
Humphreys' Ulster team mate Matt Mustchin is a late call-up to Macqueen's squad, with the 28-year-old replacing fellow New Zealander Simon Maling in the second row.
IRB TSUNAMI RUGBY AID MATCH: Saturday, March 5North v South, Twickenham, 2.30pm (live BBC 1)
(15) Chris Paterson (Edinburgh, Scotland)(14) Mirco Bergamasco (Stade Frangais, Italy)(13) Ollie Smith (Leicester, England)(12) Ceri Sweeney (Newport Gwent, Wales)(11) Ben Cohen (Northampton, England)(10) David Humphreys (Ulster, Ireland)(9) Gareth Cooper (Newport Gwent, Wales)(1) John Yapp (Cardiff, Wales)(2) Andy Titterrell (Sale Sharks, England)(3) Chris Horsman (Worcester)(4) Marco Bortolami (RC Narbonne, Italy)(5) Donncha O'Callaghan (Munster, Ireland)(6) Lawrence Dallaglio (Wasps, England) (Capt)(7) Pat Sanderson (Worcester, England)(8) Simon Taylor (Edinburgh, Scotland)
(16) Raphakl Ibanez (Saracens, France)(17) Cidric Soulette (ASM Clermont Auvergne, France)(18) Eric Miller (Leinster, Ireland)(19) Jonathan Thomas (Ospreys, Wales)(20) Mike Phillips (Llanelli, Wales)
(15) Chris Latham (Reds, Australia)(14) Brian Lima (Samoa)(13) Jacque Fourie (Cats, South Africa)(12) Tana Umaga (Hurricanes, New Zealand)(11) Sireli Bobo (Parma, Fiji)(10) Andrew Mehrtens (Crusaders, New Zealand)(9) George Gregan (Brumbies, Australia) (Capt)(1) Carl Hoeft (Highlanders, New Zealand)(2) John Smit (Sharks, South Africa)(3) Kobus Visagie (Saracens, South Africa)(4) Matt Mustchin (Ulster)(5) Victor Matfield (Bulls, South Africa)(6) Schalk Burger (Stormers, South Africa)(7) Phil Waugh (Waratahs, Australia)(8) Toutai Kefu (Kubota Spears, Australia)
(16) Ephraim Taukafa (Leicester, Tonga)(17) Eusebio Guinazu (Mendoza, Argentina)(18) Semo Sititi (Newcastle Falcons, Samoa)(19) Opeta Palepoi (Rotherham, Samoa) (20) Moses Raulini (Saracens, Fiji)(21) Tinus Delport (Worcester, South Africa) (22) Shane Drahm (Northampton)
Referee: Paddy O'Brien (New Zealand)