http://www.penturners.org/forum/topic.asp?ARCHIVE=true&TOPIC_ID=3148&SearchTerms=denim
http://www.penturners.org/forum/topic.asp?ARCHIVE=true&TOPIC_ID=3651&SearchTerms=denim
http://www.penturners.org/forum/topic.asp?ARCHIVE=true&TOPIC_ID=3866&SearchTerms=denim
Should be enough to push you in the right direction.