Mailchimp use merge tags in link url

I am building a mailchimp campaign with a link to a custom form. I would like the fields of the form to be filled in with the info I have from my suscribers (first name, last name, company name, email...) For this, I am generating custom urls with paramters for the link in the email. Those parameters are then filled in the inputs. The URLs should look like this : ``` http://www.example.com/custom_form.php? fname=some_name&lname=some_name&company=some_company$email=example@example.com ``` The issue I have is in the mailchimp editor. I want to use merge tags to generate the parameter values according to each suscriber so my link looks like this in the editor : ``` http://www.example.com/custom_form.php? fname=*|FNAME|*&lname=*|LNAME|*&company=*|COMPANY|*&email=*|EMAIL|* ``` This works fine except when for example the company name is in two words. The URL is broken and the parameters after the company name don't work. How can I encode the merge tags for urls?