[Plugin: Page Links To] Slash "/" added to end of URL

The plugin seems to automatically add a slash “/” to the end of a URL.
To illustrate:

When I want a page/post to link to an external URL I enter, for example:
http://www.example.com
Then when I click that page/post I get forwarded to:
http://www.example.com/

Strangely, this trailing slash causes some websites to not display correctly (messed-up design).

Does anyone know how to prevent the plugin to add that extra slash?

PS: I’m using the most recent version of the plugin (2.7.1).

http://wordpress.org/extend/plugins/page-links-to/