Dynamically Change Global Variables

With SQL Server 2000 DTS, we can dynamically change a global variable using the Dynamic Properties Task.
I understand that Dynamic Properties is no longer available in SQL Server 2005. How do I achieve the following?
1. I need to set the value of a global variable named "numofrecords" dynamically based on a query "select count(*) from temptable".
Previously, using Dynamic Properties Task I can just set the value property of "numofrecords" with source as Query and the writing the actual query.
2. I need to set the DataSource value of my Text File (Destination) dynamically using a global variable. Meaning, DataSource = GlobalVar (something like that).
Previously, I can set this using Dynamic Properties Task with Destination Property of DataSource, Source Type of Global Variable, Source Value of MyGlobalVariable.
Jon M

Thanks for the reply, Satya.
I also got some tips from here: http://www.mssqltips.com/tip.asp?tip=1443
Jon M