Hello Christopher

I've done some tests to find the first time this bug occur. I started the PC with different Ubuntu live CDs (every CD was a i386, desktop image). The last working distribution was 8.10 (Intrepid). The first time this bug appears was in the next version 9.04 (Jaunty). I've done this tests on several machines. The behaviour was the same on all machines so I think it's not hardware dependent. 
To make further tests I installed a *fresh* :-) Ubuntu 8.10 on a PC at my home.
After the fresh install I've done 
 sudo usermod -a -G dialout sysadmin
and relogin. 

Then I tested it again:

 sysadmin@ritsch:~$ uname -a 
 Linux ritsch 2.6.27-7-generic #1 SMP Fri Oct 24 06:42:44 UTC 2008 i686 GNU/Linux
 sysadmin@ritsch:~$ hcitool scan
 Scanning ...
	00:12:6F:08:98:FF	GEO LE-71 00001
 sysadmin@ritsch:~$ rfcomm connect 1 00:12:6F:08:98:FF            <<<--- On first time I was asked for the pin code here
 Connected /dev/rfcomm1 to 00:12:6F:08:98:FF on channel 1
 Press CTRL-C for hangup

--->>> Everything OK with vanilla 8.10 Ubuntu

In the next step I changed the apt package source in /etc/apt/sources.list 
(old-releases.ubuntu.com) and update the system to the latest available
version for 8.10 and reboot.

Then I repeat the test from above. The kernel version changed ...

 sysadmin@ritsch:~$ uname -a 
 Linux ritsch 2.6.27-17-generic #1 SMP Fri Mar 12 03:09:00 UTC 2010 i686 GNU/Linux

... but the bug is not there and everything works fine.

--->>> Everything OK with 8.10 Ubuntu with kernel 2.6.27-17

Now I decided to try to update the kernel to the same version as in the 
not working 9.04 ubuntu. The kernel version on my 9.04 CD is:

ubuntu@ubuntu:~$ uname -a 
Linux ubuntu 2.6.28-11-generic #42-Ubuntu SMP Fri Apr 17 01:57:59 UTC 2009 i686 GNU/Linux

The first try was to install the .deb packages from 9.04 on 8.10, but that don't work because
some versions mismatch (wrong libc6-version ...).
So I download the file linux-source-2.6.28_2.6.28-11.42_all.deb from 
https://launchpad.net/ubuntu/jaunty/i386/linux-source-2.6.28/2.6.28-11.42
and try to install it on the 8.10 ubuntu.
To build the new kernel I installed all essential build tools, login as root
and done the following steps:

cd
tar xjf linux-source-2.6.28.tar.bz2
cd linux-source-2.6.28
make mrproper
cp /boot/config-2.6.27-17-generic .config
make oldconfig                   <<<---- I answered all new questions with simply hit enter to use the default values
make clean
make deb-pkg
                                           ... some hours later ...
sudo dpkg -i linux-2.6.28.9_2.6.28.9-1_i386.deb
sudo dpkg -i linux-firmware-image_2.6.28.9-1_all.deb
sudo update-initramfs -u -k 2.6.28.9
sudo update-grup


The I reboot the PC and do the test again ...

sysadmin@ritsch:~$ uname -a 
Linux ritsch 2.6.28.9 #1 SMP Fri Feb 7 00:16:26 CET 2014 i686 GNU/Linux

The bug was not there!

--->>> Everything OK with 8.10 Ubuntu with kernel 2.6.28.9

I was a little bit confused, that the kernel version is 2.6.28.9. I expected 2.6.28.11 because the
package name was linux-source-2.6.28_2.6.28-11.42_all.deb ???

I'm not sure if this problem is only a kernel problem. Perhaps there are some other
things (hotplug, udev ...) which cause this bug ?

Please can you give me some hints hot to make further tests.

Greetings
Burkhard