After activating rename wp-signup.php feature the link is wrong

Hi,
Installed in my WPMS 3.0.4 Anti-Splog.
No Buddypress is installed.

The plugin instructions states:
"Replace any hardcoded links to wp-signup.php with this function: <?php ust_wpsignup_url(); ?>"

So, I modified header.php and profile.php files on EduClean them by searching and replacing wp-signup.php for the php code stated in the plugin:

<?php ust_wpsignup_url(); ?>

Then activated Rename wp-signup.php feature, clicked Save.

After doing that the link to register is very long and has the site url added twice like this:
http://comunidadespr.com/http://comunidadespr.com/signup-fca/

How do I correct the issue?

This is the code in header.php (without editing):

<div id="main-header-inner">
<?php if( is_home() && str_replace("/","",$_SERVER['REQUEST_URI']) != 'wp-signup.php' && str_replace("/","",$_SERVER['REQUEST_URI']) != 'register' ) { ?></p>
<p><div id="main-header-inner-content">
<h4><?php echo stripslashes($tn_edus_header_text); ?></h4></p>
<p><div id="intro-log">
<div id="list-benefits">
<?php echo stripslashes($tn_edus_header_listing); ?>
</div>
<div id="intro-package">
<div id="edublog-free"><h3>Añada Su Comunidad En Segundos. Es Gratis!</h3><p>/<?php if( $bp_existed == 'true' ) { //check if bp existed ?>register/<?php } else { ?>wp-signup.php<?php } ?>" title="Get yourself a free blog">Unase Ahora!</p></div>
</div>

This is the code edited (the one that creates a long url repeating the site url):

<div id="main-header-inner">
<?php if( is_home() && str_replace("/","",$_SERVER['REQUEST_URI']) != '<?php ust_wpsignup_url(); ?>' && str_replace("/","",$_SERVER['REQUEST_URI']) != 'register' ) { ?></p>
<p><div id="main-header-inner-content">
<h4><?php echo stripslashes($tn_edus_header_text); ?></h4></p>
<p><div id="intro-log">
<div id="list-benefits">
<?php echo stripslashes($tn_edus_header_listing); ?>
</div>
<div id="intro-package">
<div id="edublog-free"><h3>Añada Su Comunidad En Segundos. Es Gratis!</h3><p>/<?php if( $bp_existed == 'true' ) { //check if bp existed ?>register/<?php } else { ?><?php ust_wpsignup_url(); ?><?php } ?>" title="Get yourself a free blog">Unase Ahora!</p></div>
</div>

Please help.