I've got this to work using 2 variables, a script task and a ForEach loop container.
Variable #1 - WildCard at package scope.
Variable #2 - FileName at package scope.
Create a Script Task and set this to the wildcard desired e.g.
Code:
Dim FilePart As String
FilePart = Format(Now, "yyyyMMdd")
Dts.Variables("WildCard").Value = "abc" & FilePart & "*.date"
Create a ForEach loop container and connect the Script task to precede it.
In General: Set the folder to your folder name and ensure it is returning a fully qualified file name.
In Collection: In Foreach Loop Editor click the ellipses next to Expressions. For property select FileSpec, for expression select your variable @[User::WildCard]. Click OK.
In Variable Mappings: Select User::FileName, the index will be 0. Click OK to close.
Drag a Data Flow Task into the ForEach container.
In the Data Flow Task, create a Flat File Source. You will need an initial connection to one of your files. In the Flat file connection manager, click New and point to one of your files. Create the rest of your connection and destination as normal, then close the Flat File Source.
In Connection Manager click on the Source you just created. Click on the ellipses next to Expression. Select ConnectionString as the property and @[User::FileName] as the expression. Click OK.
What this should do is set the FileSpec property of the ForEach loop using the variable WildCard e.g. "abc20081110*.dat". This would already have been set to today's date (or whatever date you desire) using the Script Task.
When the ForEach loop finds the file(s), it will set the FileName property to the full path and name of each file it finds as it loops through.
Finally, the Source of the Flat File Source picks this up and resets the ConnectionString to the variable.
I'll look into uploading a zip file later on. This was created using BIDS on SQL 2005.