The 23-year-old Leicester lock, 6ft 8in and 19st 5lbs, qualifies for Scotland through his Glasgow-born father and impressed Hadden last season when he was part of the Barbarians squad that came to Murrayfield in May for a game the Scots won 66-19.

Hadden said: "Im keen to see how James fits in to our training programme.

"Hes a big man and athletic with it and, as Ive said already this season, competition for places is growing all the time and thats good as we gear towards the 2007 Rugby World Cup.

Hamilton, born in Swindon, played 24 times for Leicester last season, including two Heineken Cup fixtures and was part of the England under-19 squad at the 2001 Junior World Championships in Chile.

Now, however, he has decided to try to win a place in the Scotland set-up.

Hamilton said: "Ive opted to try to play for Scotland because its a personal decision from my heart.

"I like the way Scotland play and all I really want to do now is get involved with the lads at the squad session.

Hadden was given a boost when he was able to list Edinburgh back-row forwards Simon Taylor and Allister Hogg, who are both recovering from injury.

Taylor has been out since May when he damaged his knee playing against Connacht, while Hogg injured his elbow in the Magners League derby against Glasgow Warriors last month.

Hadden said: Both Simon and Ali are making excellent progress towards a comeback and could figure during the autumn Tests.

Im very much looking forward to our matches next month against Romania, the Pacific Islanders and Australia.

International rugby is back at Murrayfield and I know from speaking to the players that theyre keen to build on what we achieved last season.

Scotland squad:

Backs: Mike Blair (Edinburgh), Chris Cusiter (Border Reivers), Rob Dewey (Edinburgh), Marcus Di Rollo (Edinburgh), Phil Godman (Edinburgh), Andrew Henderson (Glasgow Warriors), Rory Lamont (Glasgow Warriors), Sean Lamont (Northampton), Ben MacDougall (Border Reivers), Calum MacRae (Border Reivers), Graeme Morrison (Glasgow Warriors), Dan Parks (Glasgow Warriors), Chris Paterson (Edinburgh), Hugo Southwell (Edinburgh), Simon Webster (Edinburgh).
Forwards: John Beattie (Glasgow Warriors), Kelly Brown (Border Reivers), David Callam (Edinburgh), Ross Ford (Border Reivers), Scott Gray (Border Reivers), Dougie Hall (Edinburgh), Jim Hamilton (Leicester), Nathan Hines (Perpignan), Allister Hogg (Edinburgh), Allan Jacobsen (Edinburgh), Alastair Kellock (Glasgow Warriors), Gavin Kerr (Border Reivers), Euan Murray (Glasgow Warriors), Scott Murray (Edinburgh), Craig Smith (Edinburgh), Simon Taylor (Edinburgh), Jason White (Sale, captain).