diff -rup Math-Algebra-Symbols-1.21.orig/lib/Math/Algebra/Symbols/Sum.pm Math-Algebra-Symbols-1.21/lib/Math/Algebra/Symbols/Sum.pm
--- Math-Algebra-Symbols-1.21.orig/lib/Math/Algebra/Symbols/Sum.pm	2004-06-15 00:25:54.000000000 +0200
+++ Math-Algebra-Symbols-1.21/lib/Math/Algebra/Symbols/Sum.pm	2012-08-28 11:08:30.000000000 +0200
@@ -1713,7 +1713,6 @@ use overload
  'sqrt'  =>\&sqrt3,
  'exp'   =>\&exp3,
  'log'   =>\&log3,
- 'tan'   =>\&tan3,
  'sin'   =>\&sin3,
  'cos'   =>\&cos3,
  '""'    =>\&print3,
diff -rup Math-Algebra-Symbols-1.21.orig/lib/Math/Algebra/Symbols/Term.pm Math-Algebra-Symbols-1.21/lib/Math/Algebra/Symbols/Term.pm
--- Math-Algebra-Symbols-1.21.orig/lib/Math/Algebra/Symbols/Term.pm	2004-06-15 00:25:54.000000000 +0200
+++ Math-Algebra-Symbols-1.21/lib/Math/Algebra/Symbols/Term.pm	2012-08-28 11:10:03.000000000 +0200
@@ -836,8 +836,8 @@ sub sqrt2($)
   my ($c, $d, $i) = ($t->{c}, $t->{d}, 0);
   $c = -$c, $i = 1 if $c < 0;
 
-  my $c2 = sqrt($c);  return undef unless $c2*$c2 == $c;
-  my $d2 = sqrt($d);  return undef unless $d2*$d2 == $d;
+  my $c2 = int(1024 * sqrt($c)) / 32;  return undef unless $c2*$c2 == $c;
+  my $d2 = int(1024 * sqrt($d)) / 32;  return undef unless $d2*$d2 == $d;
 
   my $z = clone($t)->c($c2)->d($d2)->i($i);
 
diff -rup Math-Algebra-Symbols-1.21.orig/t/bug_2004_6_5.t Math-Algebra-Symbols-1.21/t/bug_2004_6_5.t
--- Math-Algebra-Symbols-1.21.orig/t/bug_2004_6_5.t	2004-06-15 00:25:53.000000000 +0200
+++ Math-Algebra-Symbols-1.21/t/bug_2004_6_5.t	2012-08-28 11:12:16.000000000 +0200
@@ -25,5 +25,7 @@ print $y, "\n";
 
 use Math::Complex;                       # Need complex arithmetic
 $x = 2;
-my $sx = eval $y;
+my $qy = "$y";
+$qy =~ s/-/ - /g;
+my $sx = eval $qy;
 ok($sx>0.90 and $sx<0.91);