How to track changes to a table using system tables ?

I would like to get a report on a monthly basis as to what tables were
changed(from a DDL standpoint) in the last 30 days ? We add/drop/modify
columns on a regular basis. sysobjects has only crdate (object creation date)
but not modify datetime. Is there a way to get that ?
TIA
MOMO
SQL Server does not track changes like drop/modify
Visit www.dbazine.com. There you will be found a great script written by
Gregory A. Larsen (Monitoring changed objects)
"MO" <MO@.discussions.microsoft.com> wrote in message
news:0603078E-4248-419A-AA8B-C6CF0AD0D3E9@.microsoft.com...
> I would like to get a report on a monthly basis as to what tables were
> changed(from a DDL standpoint) in the last 30 days ? We add/drop/modify
> columns on a regular basis. sysobjects has only crdate (object creation
date)
> but not modify datetime. Is there a way to get that ?
> TIA
> MO