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--- a/doc/comms.txi
+++ b/doc/comms.txi
@@ -1484,56 +1484,37 @@
 @node Known Problems, , Function Overloading, Galois Field Basics
 @subsection Known Problems
-Before reporting a bug compare it to this list of known problems
+Please review the following list of known problems with the Galois type
+before reporting a bug against this package.
 @table @asis
-@item Concatenation
-For versions of Octave prior to 2.1.58, the concatenation of Galois arrays
-returns a Matrix type. That is @code{[gf([1, 0],m) gf(1, m)]} returns a
-matrix went it should return another Galois array. The workaround is to
-explicitly convert the returned value back to the correct Galois field using
-@code{gf([gf([1, 0],m) gf(1,m)],m)}.
-Since Octave version 2.1.58, @code{[gf([1, 0],m) gf(1, m)]} returns another
-Galois array as expected.
 @item Saving and loading Galois variables
-Saving of Galois variables is only implemented in versions of Octave
-later than 2.1.53. If you are using a recent version of Octave then
-saving a Galois variable is as simple as
+Saving a Galois variable to a file is as simple as
+octave:1> a = gf (@dots{});
 octave:2> save a.mat a
 @end example
-where @var{a} is a Galois variable. To reload the variable within
-Octave, the Galois type must be installed prior to a call to
-@code{load}. That is
+where @var{a} is any Galois variable. Galois variables can be saved in the
+Octave binary and ASCII formats, as well as the HDF5 format. To load a
+Galois variable from a file, the Galois type must already be registered to
+the Octave interpreter prior to the call to @code{load}. If no Galois
+variables have been created yet, you will have to do something like
 octave:1> dummy = gf (1);
 octave:2> load a.mat
-@end example
-With versions of Octave later than 2.1.53, Galois variables can be
-saved in the Octave binary and ASCII formats, as well as the HDF5
-format. If you are using an earlier version of Octave, you can not
-directly save a Galois variable. You can however save the information
-it contains and reconstruct the data afterwards by doing something
-octave:2> x = a.x; m = a.m; p = a.prim_poly;
-octave:3> save a.mat x m p;
 @end example
 @item Logarithm of zero does not return NaN
 The logarithm of zero in a Galois field is not defined. However, to avoid
 segmentation faults in later calculations the logarithm of zero is defined
 as @code{2^@var{m} - 1}, whose value is not the logarithm of any other value
-in the Galois field. A warning is however printed to tell the user about
-the problem. For example
+in the Galois field. A warning is also shown to tell the user about the
+problem. For example
 octave:1> m = 3;
@@ -1552,9 +1533,8 @@
 exceptions will certainly slow the code down.
 @item Speed
-The code was written piece-meal with no attention to optimum code. Now
-that I have something working I should probably go back and tidy the
-code up, optimizing it at the same time.
+The code was written piecemeal with no attention to optimization. Some
+operations may be slower than they could be. Contributions are welcome.
 @end table
@@ -1649,14 +1629,13 @@
 within the Galois field. In this case they will be assumed to be of the
 same field.
-As Octave supports concatenation of typed matrices only for version
-2.1.58 and later, matrix concatenation will force the Galois array back
-to a normal matrix for earlier version. For instance for Octave 2.1.58
-and later.
+Galois arrays can also be concatenated with real matrices or with other
+Galois arrays in the same field. For example
 octave:1> a = [gf([0:7], 3); gf([7:-1:0], 3)];
 octave:2> b = [a, a];
+octave:3> c = [a, eye(2)];
 octave:3> whos
 Variables in the current scope:
@@ -1664,37 +1643,12 @@
    ==== ====        ====                     =====  ===== 
         a           2x8                         64  galois
         b           2x16                       128  galois
-Total is 48 elements using 192 bytes
-@end example
-and for previous versions of Octave
-octave:1> a = [gf([0:7], 3); gf([7:-1:0], 3)];
-octave:2> b = [a, a];
-octave:3> whos
-*** local user variables:
-prot  type                       rows   cols  name
-====  ====                       ====   ====  ====
- rwd  matrix                        2      8  a
- rwd  matrix                        2     16  b
-@end example
-This has the implication that many of the scripts included with Octave
-that should work with Galois fields, won't work correctly for versions
-earlier than 2.1.58. If you wish to concatenate Galois arrays with earlier
-versions, use the syntax
-octave:1> a = gf ([0:7], 3);
-octave:2> b = gf ([a, a], a.m, a.prim_poly);
-@end example
-which explicitly reconverts @var{b} to the correct Galois Field. Other
-basic manipulations of Galois arrays are
+        c           2x10                        80  galois
+Total is 68 elements using 272 bytes
+@end example
+Other basic manipulations of Galois arrays are
 @table @code
 @item isempty

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