Activex Question

I'm attempting to write my first activex script. Not familiar with VB script so bear with what might seem like a simple question.

I'm trying to use an activex script in a dts to do a transformation. I have all the columns as straight copies except for one which I'm doing an activex script. What I'm trying to do is if the date is less than 1900-01-01 I want to default it to 1900-01-01. Every once in awhile a date comes across from the source file with a date of 0001-01-01 which sql doesn't like so I want to default it to 1900-01-01 instead. The script I've created parces fine but when I run the dts I get an error that the activex script encountered an invalid data value for source column LLAI. I don't understand why. any suggestions would be greatly appreciated.

Here is the script.

Function Main()
If DTSSource("LLAI") >= "1900-01-01" Then
DTSDestination("LastActivityISODate") = DTSSource("LLAI")
Else
DTSDestination("LastActivityISODate") = "1900-01-01"
End If

Main = DTSTransformStat_OK

End Function