I don't see any big problems at all. Here are some minor suggestions for improvements.

I believe you have a typo in your warn message: change 'characted' to 'character'.

You should indent the code in the 'Code Sample' section of the SYNOPSIS in your POD. When I use perldoc, it renders poorly for me. You should also remove the tab characters in that code example because it still renders poorly even after I indented it.

You should add more data validation for your input. If I do something that you probably don't expect, I do get lots of warnings, but they could be more helpful. I tried this (probably) illegal thing, and I got about 20 warnings: 

my $foo = $gsm->decode_7bit_wlen(5);

[download]
Of course, that means you should add tests to your test suite. The Perl Best Practices book has a nice, succinct checklist of general-purpose things to test.

As a user, I absolutely love it when a CPAN author includes a script I can run out-of-the-box, preferably in the bin directory, or at least in the examples directory. This could be nothing more than the code from the SYNOPSIS.

There are plenty more style suggestions if you run the code through perlcritic.

Update: Do this before you upload your tar file: Fix CPAN uploads for world writable files

You should delete the INSTALLATION section from the POD. There is no need to tell someone how to install something which has already been installed.

Another typo: change 'costructor' to 'constructor'. I guess you should run your code through a spell-checker.

In reply to Re: RFC: Module - GSM::Nbit by toolic
in thread RFC: Module - GSM::Nbit by techcode

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