Can't really help you troulbeshoot your serial port, but when I gave my Rocket Ebook to my folks, I also got the one of these:
http://www.buy.com/retail/product.as...43&dcaid=17902
because their machine didn't have a serial port. This worked well for connecting the Rocket via USB.
Can't make any guarantees
, but if you can't get the serial port to work, it's an option to try.