Comment 14 for bug 374782

Verify /dev/rfcomm0 is rwx using ls.
Also try "cat /dev/rfcomm0" and/or "wc /dev/rfcomm0" to see if they give errors.
You might also want to try the above with "strace" preceeding the command just to see the open, and/or with "sudo"

I normally have to start "rfcomm connect 0 <btaddr>" before it goes live - there is a way to give the address in a config file and maybe do it automatically but I've always done it from the command line.

This program must automatically create /dev/rfcomm0. Simply pairing the device and doing mknod will not associate the network pipe with the device node.