Dear Forum,

We have encountered the following problem:

gap> a:=Group( (1,2,3,4));
Group( (1,2,3,4) )
gap> b:=Group((5,6,7,8));
Group( (5,6,7,8) )
gap> g:=GroupHomomorphismByImages(a,b,a.generators,b.generators);
GroupHomomorphismByImages( Group( (1,2,3,4) ), Group( (5,6,7,8) ),
[ (1,2,3,4) ], [ (5,6,7,8) ] )
gap> KernelGroupHomomorphism(g);
Subgroup( Group( (5,6,7,8) ), [  ] )

As you can see, gap aims, that this kernel is a subgroup of g.range
instead of g.source. The problem is (we hope) only in the case if g is a
bijection.
Is it enough to change lines

else
           hom.kernel := TrivialSubgroup( Parent(hom.range) );
                                                     ^^^^^
       fi;
   fi; #  not IsBound(hom.inverseMapping.orbit) or not IsBound(hom.kernel)

to lines

else
           hom.kernel := TrivialSubgroup( Parent(hom.source) );
                                                     ^^^^^^
       fi;
   fi; #  not IsBound(hom.inverseMapping.orbit) or not IsBound(hom.kernel)

in premhomo.g file (this seems to be the only convenient place, but we
may fail)?

Thank you

Jaroslav Gurican, Martin Macaj