diff --git a/library/test/math/integer.factor b/library/test/math/integer.factor
index b8aa39ae99..67702a865e 100644
--- a/library/test/math/integer.factor
+++ b/library/test/math/integer.factor
@@ -67,7 +67,7 @@ USING: kernel math namespaces prettyprint test ;
 [ 134217728 dup + dup + dup + dup + dup + dup + unparse ]
 unit-test
 
-[ 0.0/0.0 ] [ 0 0 ^ ] unit-test
+[ t ] [ 0 0 ^ fp-nan? ] unit-test
 [ 1 ] [ 10 0 ^ ] unit-test
 [ 1/8 ] [ 1/2 3 ^ ] unit-test
 [ 1/8 ] [ 2 -3 ^ ] unit-test
diff --git a/library/test/math/irrational.factor b/library/test/math/irrational.factor
index c614bb0215..9aecd83d82 100644
--- a/library/test/math/irrational.factor
+++ b/library/test/math/irrational.factor
@@ -17,9 +17,9 @@ USE: test
 [ t ] [ e pi i * ^ real -1.0 = ] unit-test
 [ t ] [ e pi i * ^ imaginary -0.00001 0.00001 between? ] unit-test
 
-[ 0.0/0.0 ] [ 0 0 ^ ] unit-test
+[ t ] [ 0 0 ^ fp-nan? ] unit-test
 [ 1.0/0.0 ] [ 0 -2 ^ ] unit-test
-[ 0.0/0.0 ] [ 0 0.0 ^ ] unit-test
+[ t ] [ 0 0.0 ^ fp-nan? ] unit-test
 [ 1.0/0.0 ] [ 0 -2.0 ^ ] unit-test
 [ 0 ] [ 0 3.0 ^ ] unit-test
 [ 0 ] [ 0 3 ^ ] unit-test
diff --git a/version.factor b/version.factor
index b3dbef5364..cd4fdfd04d 100644
--- a/version.factor
+++ b/version.factor
@@ -1,2 +1,2 @@
 IN: kernel
-: version "0.80" ;
+: version "0.81" ;