Hi,
I am running kamikaze 7 on a RB532 board, and an instrument connected to
its serial port. By telnetting to the RB532 board, how do I control/access the
instrument in the serial port ? Are there any application available .....
any ideas would be appreciated .....

thanks,

Try minicom, picocom, etc.

what i'am looking for is an app that allows me to access the device connected to teh the serial port of the
rb532 using network connections. something like network-> serial or in that means .....

I don't know of anything like that, but you need to give more information.  What protocol is used to talk from the rb532 to the other device over the serial cable?  What protocol do you want to use to talk over the network to the rb532?

From what you have said, you could use SSH over the network to the rb532.  In the SSH session, run minicom or something similar and type commands that get sent over the serial line.  If this is not what you want, you will need to explain better what it is you want

Finally I found what I was looking for ...that is ser2net...it might help someone in the futture .....
ser2net allows to connect to an instrument connected to a serial port of another instrument/computer/etc using LAN...
works like this: telnet <ip> <special port> ip address here is the ip of the instrument that can be accessible via network ...