Trying to give something back to the Community...
Can I slipstream Service Pack 2? [27/10/09] Contributed By: Cliff Hobbs [MVP ConfigMgr]
In a word no. Microsoft has no plans to allow you to create your own ConfigMgr installation media slipstreamed with SP2. So your options are either:
Read the complete post at http://wmug.co.uk/blogs/cliffs_blog/archive/2009/10/27/configmgr-new-faqshop-article-27th-oct-09.aspx