When first commiting a file to Subversion the executable property is set (based on the files x property). If script file etc are mistakinly added/commited with this property incorrectly set it has to be manually altered so that they are executable when others check out the repository.
A more complete explanation is given in the link but below is a quick example of how to fix this:
$ ls -l run_some_script.sh
>-rw-rw-r-- 1 user group 2248 Mar 17 16:45 run_some_script.sh
$ svn propset svn:executable run_some_script.sh
>property 'svn:executable' set on 'run_some_script.sh'
$ls -l run_some_script.sh
>-rwxrwxr-x 1 user group 2248 Mar 17 16:45 run_some_script.sh*
To remove an incorrectly set Executable property:
$ svn propdel svn:executable file
>property 'svn:executable' deleted from 'file'