English (not American) Idiom ) non-LBC

[Ct54531@aol.com]

Listers across the pond:

I'm reading a novel by one of my favo(u)rite authors, Clive Egleton. In it, 
he is describing certain departments of the SIS and refers to one as "nothing 
short of a dog's breakfast".  I can usually figure these things out but that 
one has me stumped. 
What does it mean? And being a bit of an amateur etymologist, what's the 
origin of it?  
Thanks.

Jim 
CT54531L
65 4A