mate error

Since updating to 2009, I and another guy here have noticed apurple dashed line when we have some sort of mate error in ourassembly.
I glanced through the "what's new for 2009", but didn't findanything explaining what it means.
Could I have one of the solidworks guru's here tell me what it isI'm seeing?
Thanks so much for all your help.SolidworksAssemblies