[gembud] Text rotation not working

Hello everyone,

I am trying to make use of the text rotation option in GEMPAK.  According
to the documentation,
     "The text rotation is a character input that specifies whether the
      text is aligned with the screen (S) or with north (N) on a given
      image. If the choice is invalid or not specified, the current value
      will be used."
which is given in the fifth option in TEXT.  To test out the text alignment
option towards the north, I tried plotting a map of North America with
lat/lon lines using GPMAP with TEXT=1/21/1/1/N/C.  However, the lat/lon
labels remain aligned with the screen and not parallel with latitude
lines.  Is there something I have missed?

Thanks for your help.

 MAP      = 1
 MSCALE   = 0
 GAREA    = ncna
 PROJ     = str/90;-105;0
 LATLON   = 1
 PANEL    = 0
 TITLE    = 0
 TEXT     = 1/21/1/1/N/C
 CLEAR    = y
 DEVICE   = xw