Cannot install on a server with multiple addons path

[sinoj]

default_get on installer.py generate error on installing a server with multiple addons (coma seperated) folder.

Traceback (most recent call last):
  File "/opt/openerp/server/bin/osv/osv.py", line 57, in wrapper
    return f(self, dbname, *args, **kwargs)
  File "/opt/openerp/server/bin/osv/osv.py", line 140, in execute
    res = pool.execute_cr(cr, uid, obj, method, *args, **kw)
  File "/opt/openerp/server/bin/osv/osv.py", line 130, in execute_cr
    return getattr(object, method)(cr, uid, *args, **kw)
  File "/opt/openerp/addons/outlook/installer.py", line 35, in default_get
    file = open(config['addons_path'] + "/outlook/plugin/openerp-outlook-plugin.zip", 'r')
IOError: [Errno 2] No such file or directory: '/opt/openerp/addons,/opt/openerp/addons-jdc,/opt/openerp/addons-extra/outlook/plugin/openerp-outlook-plugin.zip'