Hi,
I was using till yesterday LG 2130 , and from today onwards i have shifted with NOKIA 2112, initially i was very much reluctant to go for NOKIA as i use rconnect heavily. But after veryfing the technical details and some features i decided to go for 2112. I used the DKU -5 Cable which i was using for my GSM NOKIA 6610i, I did not face any problem. Regarding CA 42 and DKU 5 Cable if you are confused better have both the driver from Reliance website as well as from Nokia website, I will suggest you to download Nokia PC Suite also.
Most of the time people are making mistake while installing the driver for USB ( it should be proper and for particular operating system , if not sure try to install OEM driver). I am getting speed sometimes more than 115 Kbps which was not possible in LG RD 2130.
I hope this information will be of some help.
feel free to talk to me
Thanks
bye