Description of problem:
exo-compose-mail-1 fails to execute the generated command.

Version-Release number of selected component (if applicable):
Nom                 : exo
Architecture        : x86_64
Version             : 0.10.2
Révision            : 8.el7

How reproducible:
Always

Steps to Reproduce:
1. Open default mail client (e.g. Thunderbird)
2. Open a terminal and run the following command:
$ /usr/lib64/xfce4/exo-1/exo-compose-mail-1 mozilla-remote /usr/bin/thunderbird foo

Actual results:
Nothing happens.
Running pdb shows that the script exits at line 171 while trying to execute the command built:
/usr/bin/thunderbird -remote xfeDoCommand(composeMessage,to='foo',cc='',bcc='',attachment='')
Running this command directly from the shell produces the expected result.

Expected results:
Opening a new mail window in the default client with headers filled using parameters to the mailto URI.

Additional info:
Replacing the Python script by the original Perl version solves the issue.