Problem in connecting beagle board xm

I need to connect beagle board to pc using usb for android development. But when i connect it doesn’t get recognized by ‘lsusb’.
Whatever i have read about this, according to that it should get detected as a ttyUSB*. but its not shown by ‘lsusb’.
I have followed this post too… http://ubuntuforums.org/showthread.php?t=1325846.
I am using Linux mint 64 bit.

Outputs are as follows–>

 $ lsmod | grep ftdi_sio

----> No output

$ sudo modprobe ftdi_sio
$ lsmod | grep ftdi_sio

output---->

 
        ftdi_sio               48930  0 
        usbserial              45014  1 ftdi_sio
$ dmesg | grep -i ftdi
[19067.609686] usbcore: registered new interface driver ftdi_sio
[19067.609698] usbserial: USB Serial support registered for FTDI USB Serial Device

No output for->

 $ lsusb | grep -i ft

When i try to access using Putty with 192.168.7.2, it shows no route to the host!