diff --git a/Scripting-faq.md b/Scripting-faq.md
index ca7cf9b..1aecac0 100644
--- a/Scripting-faq.md
+++ b/Scripting-faq.md
@@ -21,4 +21,16 @@ line 1: syntax error, unexpected tGVAR
 Aliasing global variables using alias statement is out of ISO scope.
 it's mruby limitation.
 
-See also [mruby/issues#1154](https://github.com/mruby/mruby/issues/1154).
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+See also [mruby/issues#1154](https://github.com/mruby/mruby/issues/1154).
+
+## Division by zero does not raise error.
+```
+> 1 / 0
+ => inf
+> 1 % 0
+ => NaN
+> 0 / 0
+ => NaN
+```
+This behavior is an ISO incompatible feature. See
+[mruby/pull#492](https://github.com/mruby/mruby/pull/492) and [mruby/pull#1907](https://github.com/mruby/mruby/pull/1907) .
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