Aston Villa's Darius Vassell picked up a knee injury in a friendly.
"Darius Vassell played in Dubai on Wednesday night with the permission of Sven who had a previous arrangement with David O'Leary," said FA spokesman Adrian Bevington.
"Alan Smith has now been called up into the squad and joined up with them on Thursday evening."
Smith has six England caps to his name but has not featured in the squad since his red card against Macedonia at Southampton's St Mary's Stadium over a year ago.
Full England 22-man Squad;
GOALKEEPERS
David James
Paul Robinson
Ian Walker
DEFENDERS
Wayne Bridge
Ashley Cole
Anthony Gardner
Glen Johnson
Danny Mills
Gary Neville
Phil Neville
John Terry
Matthew Upson
MIDFIELDERS
David Beckham
Nicky Butt
Joe Cole
Jermaine Jenas
Frank Lampard
Danny Murphy
Scott Parker
STRIKERS
Emile Heskey
Wayne Rooney
Alan Smith
It will be the first time the two national teams have met since the World Cup in June 2002 when England ran out easy 3-0 winners in the Second Round.
The last time the Danes were in England was in 1994 when David Platt's goal earned a 1-0 victory at Wembley.
The last time the Danes were in England was in 1994 when David Platt's goal earned a 1-0 victory at Wembley.