GAP4, Version: 4r2 of 29-Feb-2000, i686-pc-linux-gnu-gcc
gap> R := Integers mod 9;
(Integers mod 9)
gap> S := FullMatrixAlgebra(R,2);
( (Integers mod 9)^[ 2, 2 ] )
gap> Units(S);
Segmentation fault
Maybe I need a patch?

All the best,
George

And I have installed all 8 bugfixes, but I have:

GAP4, Version: 4r2 fix8 of 7-June-2001, i686-pc-cygwin-gcc
Components: small, small2, small3, small4, small5, small6, small7,
small8, id2, id3, id4, id5, id6, trans, prim, tbl,
tom installed.
gap> LogTo("bug.txt");
gap> R:=Integers mod 9;
(Integers mod 9)
gap> S:=FullMatrixAlgebra(R,2);
( (Integers mod 9)^[ 2, 2 ] )
gap> Units(S);
Error, no method found! For debugging hints type ?Recovery from NoMethodFound
Error no 1st choice method found for `PROD' on 2 arguments at
Error( no_method_found );
<compiled or corrupted call value> called from
IsUnit( R, elm ) called from
<function>( <arguments> ) called from read-eval-loop
Entering break read-eval-print loop, you can 'quit;' to quit to outer loop,
or you can return to continue

Sincerely yours,
Alexander B. Konovalov
Ph.D., Associate Professor, Algebra & Geometry Chair
Department of Mathematics & Economy Cybernetics
Zaporozhye State University, Zaporozhye, Ukraine
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E-mail: algebra@hotmail.zp.ua, konovalov@member.ams.org
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