It signifies the presence of an Samsung S-PVA panel on Samsung smaller sets. Many manufactuerers for the past few years use different panels on the same model LCD televisions especially in 42" and smaller sets.
Interestingly enough, Ihe Samsung S-PVA panels Ive seen on the 40EH5000 are 8th generation, which is fairly old. I think Samsung is up to 11th generation factory with different LCD subpixel structures.
It looks like this...
These were new about 2006-2007.