It might be that you need to scan one of the configuration barcodes from one of the Symbol manuals (LS3408, DS6607, etc). Many Symbol scanners seem to use similar barcodes to configure. I suspect that the Scan Suffix configuration barcode may be needed. This would allow the scanner to send a CR after the barcode data where the application could detect that and act accordingly.
It was not mentioned if the scanner was USB or serial type (for serial, you might check
http://scanagent.dyndns.biz).