strange behaviour in plain text email

Hi.

I have a link to register with a token in a plain text email file.

The link looks like this

http://someurl/register?token=123456789

However, the link in the email looks like this

http://someurl/register?token=3D123456789 - there is an extra 3D in there for some reason…

The mailer function looks like this:

def invitation(invite,user)
@subject = “#{user.login} invited you to join”
link_string = “http://someurl.com/register?token=” + invite.register_token.to_s
body :user => user, :invite => invite, :reg_link => link_string
recipients invite.email
from Settings.email_form || "me@home.com
"
content_type “text/plain”
end

The line in the email is just <%= @reg_link %> and the file is called invitation.text.plain.rhtml.

Will appreciate any feedback

Regards

Ivor