Using layers in Rgraphviz - r

Question

In Rgraphviz, how can I assign nodes and edges to particular layers, and plot only a selected layer or layers?
After perusing and searching the Rgraphviz documentation, I think I've figured out how to assign nodes and edges to particular layers -- but I still can't figure out how to plot only a selected layer.
This "How to use layers" item on the graphviz wiki implies that there should be a "layerselect" graph attribute that can be used to plot only a specified layer. However, the list of allowed graph attributes in Rgraphviz does not include "layerselect." The "layers" graph attribute says "Only those components belonging to the current layer appear," but I can find no information on how to set (or even query) the "current layer."
I tried to do it anyway, but wasn't successful. Here's a reproducible example of my attempt:
require('Rgraphviz')
params <- LETTERS[1:5] #nodes A, B, C, D, E
edgelist <- vector('list', #set up edges
length=length(params))
names(edgelist) <- params
edgelist[['B']] <- c('E','A') #add edges from B to E and from B to A
edgelist[['A']] <- 'C' #add edge from A to C
edgelist[['D']] <- 'E' #add edge from D to E
graph.nel <- new('graphNEL', #construct graphNEL object
nodes=params,
edgeL=edgelist,
edgemode='directed')
#I want there to be two layers:
#"redlayer", containing nodes A, B, C, E and the edges between them;
#"blacklayer", containing node D and the edge from D to E.
#Assign the colors and layers of the edges
eAttr <- list(color=c('B~A'='red',
'A~C'='red',
'B~E'='red',
'D~E'='black'),
layer=c('B~A'='redlayer',
'A~C'='redlayer',
'B~E'='redlayer',
'D~E'='blacklayer')
)
#Assign the colors and layers of the nodes
nAttr <- list(color=c(B='red',
A='red',
C='red',
E='red',
D='black'),
layer=c(B='redlayer',
A='redlayer',
C='redlayer',
E='redlayer',
D='blacklayer'))
#Now plot
plot(graph.nel,
attrs=list(graph=list(layers='redlayer:blacklayer', #Define the two layers
layersep=':', #Explicitly define the layer separation character
layerselect='redlayer')), #Attempt to select only the 'redlayer' for plotting
edgeAttrs=eAttr, #specify edge attributes
nodeAttrs=nAttr #specify node attributes
)
The result of the above code is the following plot:
However, I expected that only the nodes and edges colored red (i.e. those assigned to the layer named 'redlayer') would appear!
I've also tried
plot(graph.nel,
attrs=list(graph=list(layers='redlayer'), #Attempt to select only the 'redlayer' for plotting
edgeAttrs=eAttr, #specify edge attributes
nodeAttrs=nAttr #specify node attributes
)
but it results in exactly the same plot -- that is, both layers are still being plotted.
Is there any way to plot only the layer named 'redlayer' in this example?