Well seems that the official davis cup website has Murray playing against Federer in the first singles match after the doubles match, god i hope this is right.
http://www.daviscup.com/news/newsarticle.asp?id=13366The draw for the Davis Cup by BNP Paribas World Group play-off tie between Switzerland and Great Britain in Geneva has been made:
Roger Federer (SUI) v Alan Mackin (GBR)
Stanislas Wawrinka (SUI) v Andrew Murray (GBR)
Yves Allegro/Roger Federer (SUI) v Andrew Murray/Greg Rusedski (GBR)
Roger Federer (SUI) v Andrew Murray (GBR)
Stanislas Wawrinka (SUI) v Alan Mackin (GBR)
dont know if this could change depending on results in the first 3 matches lets hope it does happen