Truncated urls in content

If I include links in the content of my mails, like http://www.test.com/index.php?action=gallery;cat=10, and I follow the link, it sends me instead to a truncated link like http://www.test.com/index.php?action=gallery;cat

Any ideas, why this happens?

Thanks.

@yameth You should use & instead of ; as the separator. There is a lot of code in phplist that expects & (or sometimes &) to be the separator.

Thanks duncanc! It worked.
It is a little unorthdox though to have edit each url.
But no biggie.