Invisible ConcurrentModificationException thrown when PacketListener removes itself

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Add a packetListener that prints some string and the response,
    and then removes itself (you can grab any example suitable to your env)
2. Add another packet listener that prints another string and the response
3. Communicate with a sensor.

What is the expected output? What do you see instead?
In the 1st notification, output from both packet listeners is printed; 
subsequently only the one from the second.

Instead, in the first notification, only output from the 1st pl is printed 
(after that, a swallowed CME prevents calling the second. Subsequently, the 

What version of the product are you using? On what operating system?
I'm using version f49adc0eebfe.

Please provide any additional information below.
I have created a clone containing a proposal for a fix:
https://code.google.com/r/hartmutbenz-xbeeapi/source/detail?r=a1590a02637d581267
cc3503d4ee846cc60fecc6&name=development

Original issue reported on code.google.com by hartmut....@gmail.com on 6 Jul 2014 at 1:37

[GoogleCodeExporter]

I have recently collected a few bug fixes in a branch bugFixedForUpstream 
(https://code.google.com/r/hartmutbenz-xbeeapi/source/list?name=bugFixedForUpstr
eam), which now also contains a proposal to fix this issue (f42333d88dce).

Original comment by hartmut....@gmail.com on 18 Oct 2014 at 9:29