HP Digital Sender Firmware update

I cannot update from Firmware 1.001 to 3.004e.
Normaly you have to use the Enterprise Center to update but you can only use it from Ver 1.3. Therefore I have to use the JetAdmin Software but I can only import files
witht the ending .ver and I can only download .tgz files from the HP web page.
How can I update the firmware?