[R-sig-Geo] Error in multiple && !outer : invalid 'x' type in 'x && y'

[Jim Burke]

Thanks in advance everyone. I need assistance
resolving the above error. Trying to spplot join
or merge two "SpatialPolygonsDataFrame"s

Each set of polys will plot adjacent to each other.
They do not overlap.

census_block_sp <- readShapePoly("HD_108_blocks_sp.shp", 
IDvar="BLKIDFP", proj4string=CRS("+proj=aea +ellps=GRS80 +datum=WGS84"))
tx3_sp <- readShapePoly("HD_108_whole_sp.shp", IDvar="PCT", 
proj4string=CRS("+proj=aea +ellps=GRS80 +datum=WGS84"))


spplot(tx3_sp, c("D_TOT"),
    colorkey=list(height=1.0, width=0.6),
    main = list(label="HD-108 - Barack Obama \n Votes by Precinct 
11/04/08",cex=1),
    sub =  list(label="by Jim Burke, j.burke at earthlink.net",cex=.3),
    line=0,
    sp.layout = list("sp.text",coordinates(tx3_sp),
                    as.character(tx3_sp$PCT,cex = .02),
                    as.table = TRUE),
                list("sp.text", coordinates(census_block_sp),
                    as.character(census_block_sp$NAME, cex = .02),
                    col='blue')     
)

Error in multiple && !outer : invalid 'x' type in 'x && y'

Thanks,
Jim Burke