Need to allow @ in the URI string

[eluser]Unknown[/eluser]
I'm developing a REST app and one of the capabilities is to be able to register a user. Of course I'll need a valid email address but CI rejects the '@' sign.

I tried changing the $config['permitted_uri_chars'] to these values to no avail:
$config['permitted_uri_chars'] = 'a-z 0-9~%.:_\@\-';
$config['permitted_uri_chars'] = 'a-z 0-9~%.:_@-';
$config['permitted_uri_chars'] = 'a-z 0-9~%.:_\-@';
$config['permitted_uri_chars'] = 'a-z 0-9~%.:_\-\@';

heck I even tried $config['permitted_uri_chars'] = '' and nothing is changing

Suggestions?

[eluser]pistolPete[/eluser]
Why do you need to pass the email address via URI instead of using a POST request?

[eluser]Unknown[/eluser]
[quote author="pistolPete" date="1253033229"]Why do you need to pass the email address via URI instead of using a POST request?[/quote]

It's a client requirement, I'm not privy of what happens beyond. I do think that it's quite overkill for a simple registration procedure to make use of a REST server but then I don't know of the big picture.

But I found the solution, the $config['uri_protocol'] is being modified by the REST library I am using. Client wants to register users with the use of my REST server so that's the case.

OK problem solved. Thanks pistolPete for the reply.