From: Gavin Kistner <gavin.kistner@...>
Date: 2006-09-22T04:02:41+09:00
Subject: Re: Calculate last day of month

> How do I return the date for the last day of this month (September in 
> this example)?

The last day in a month is the day before the first day in the next
month.

require 'date'
d = Date.new( 2006, 10, 1 )
puts d-1
#=> 2006-09-30