Yes, this is perfectly normal on a 320d...!
I'm currently waiting for a replacement clutch from BMW to arrive at my dealer.
There is a new modified unit coming out, Rich1068 has one on his car. Mine is due at the end of February.
There is a topic which covers this, think it's call Clutch Judder ... a fix? on page 5
http://www.e90post.com/forums/showthread.php?t=597629
Gives loads of info for you to peruse
HTH