diff -uNr gphys-1.0.0_old/lib/numru/ggraph.rb gphys-1.0.0/lib/numru/ggraph.rb
--- gphys-1.0.0_old/lib/numru/ggraph.rb	2010-02-18 17:08:06.000000000 +0900
+++ gphys-1.0.0/lib/numru/ggraph.rb	2010-02-22 11:14:29.000000000 +0900
@@ -876,6 +876,7 @@
                              # margin even when newframe==true
        "ltone"       true    # Same as udpack parameter ltone
        "tonf"        false   # Use DCL.uetonf instead of DCL.uetone
+       "tonb"        false   # Use DCL.uetonb instead of DCL.uetone
        "tonc"        false   # Use DCL.uetonc instead of DCL.uetone
        "clr_min"     nil     # if an integer (in 10..99) is specified, used as
                              # the color number for the minimum data values.
@@ -4193,6 +4194,7 @@
           ['lomax', nil, 'maximam longitude value'],
           ['ltone', true, 'Same as udpack parameter ltone'],
           ['tonf', false, 'Use DCL.uetonf instead of DCL.uetone'],
+          ['tonb', false, 'Use DCL.uetonb instead of DCL.uetone'],
           ['tonc', false, 'Use DCL.uetonc instead of DCL.uetone'],
           ['clr_min', 13,  'if an integer (in 10..99) is specified, used as the color number for the minimum data values. (the same can be done by setting the uepack parameter "icolor1")'],
           ['clr_max', 99,  'if an integer (in 10..99) is specified, used as the color number for the maximum data values. (the same can be done by setting the uepack parameter "icolor2")'],
@@ -4611,6 +4613,7 @@
       ['ltone', true, 'Same as udpack parameter ltone'],
       ['auto', false, 'Swith DCL.uetone and DCL.uetonf depending on the data size'],
       ['tonf', false, 'Use DCL.uetonf instead of DCL.uetone'],
+      ['tonb', false, 'Use DCL.uetonb instead of DCL.uetone'],
       ['tonc', false, 'Use DCL.uetonc instead of DCL.uetone'],
       ['clr_min', nil,  'if an integer (in 10..99) is specified, used as the color number for the minimum data values. (the same can be done by setting the uepack parameter "icolor1")'],
       ['clr_max', nil,  'if an integer (in 10..99) is specified, used as the color number for the maximum data values. (the same can be done by setting the uepack parameter "icolor2")'],
@@ -4679,6 +4682,8 @@
       if ( opts['ltone'] && 
           ( opts['tonf'] || opts['auto'] && val.length > TONE_TONF_THRES ) )
         DCL.uetonf(val)
+      elsif opts['tonb'] && opts['ltone']
+        DCL.uetonb(val)
       elsif opts['tonc'] && opts['ltone']
         DCL.uetonc(val)
       else