[R-sig-Geo] Error when accessing raster layer (package 'raster')

[Johannes Radinger]

Hi,

I have a rasterbrick and when I try to access a single layer of it I
get following error:
>  my_brick[["layer_1"]]
class       : RasterLayer
dimensions  : 912, 840, 766080  (nrow, ncol, ncell)
resolution  : 50, 50  (x, y)
extent      : 3505300, 3547300, 6025800, 6071400  (xmin, xmax, ymin, ymax)
coord. ref. : +proj=tmerc +lat_0=0 +lon_0=9 +k=1 +x_0=3500000 +y_0=0
+ellps=bessel +datum=potsdam +units=m +no_defs
+towgs84=598.1,73.7,418.2,0.202,0.045,-2.455,6.7
values      : in memory
layer name  : layer_1
min value   : 0
max value   : 0.1841621
Error in if (is.factor(object)) { : missing value where TRUE/FALSE needed

The rasterbrick is created by a rasterstack (approx. 15 layers) that
is masked using the function mask.
When I try to access the same layer in the unmasked rasterstack I
don't get the error.

Any suggestions?

I am using R 2.15.2 with raster 2.0-08 (27-June-2012) on Ubuntu.

best regards,
/Johannes