sorry for the interrupted post - the electrician suddenly needed to turn the power off NOW and I foolishly hit "submit" instead of waiting to start again later.
According to the guinealynx forage list, white clover is OK, but may cause gas in large amounts and is a source of calcium. And Ly&Pigs says that both white and red clover are OK in this thread
http://www.cavycages.com/forum/showthread.php?t=16100
I've read on another forum that red clover should be limited, but the clover in our garden is all white anyway and I always restrict it for the reasons given above.
I have a friend who takes a supplement made from red clover for menopause symptoms so I wondered whether it had any other active constituents that meant it should be fed in limited quantities?