Quick Chain Length Question

I have one set of wheels with (10 speed)105 cassette of 12/25 have just got some more wheels which I want to put a 11/23 Ultegra cassette on them. Will I need to adjust the chain length or not. I will be shifting between the wheelsets on a fairly regular basis.
Norfolk, who nicked all the hills?
http://farm4.static.flickr.com/3013/243 ... 8d.jpg?v=0
http://img362.imageshack.us/my.php?imag ... 076tl5.jpg
http://img216.imageshack.us/img216/3407 ... e001af.jpg
http://farm4.static.flickr.com/3013/243 ... 8d.jpg?v=0
http://img362.imageshack.us/my.php?imag ... 076tl5.jpg
http://img216.imageshack.us/img216/3407 ... e001af.jpg
0
Posts
http://farm4.static.flickr.com/3013/243 ... 8d.jpg?v=0
http://img362.imageshack.us/my.php?imag ... 076tl5.jpg
http://img216.imageshack.us/img216/3407 ... e001af.jpg