You may also want to check the metadata in SSIs to see if it "guessed" incorrectly as to the underlying data types. If it had to derive the types rather than getting from an authoritative source - it probably "guessed" that that column is supposed to be a 2-byte integer.

To see what it picked - open up the properties on the xml file connector, one of the tabs there shows what was done (input/output types as I recall). You can then override the guess to an appropriate data type (pretty sure there is a flag you can throw on the connection string to prevent it from guessing but I cannot recall what that is right now).