Due to my theme requirement I have to override theme_link() function in my temeplate.php file. I have to wrap my link text in extra span

function theme_link($variables) {
  return '<a href="' . check_plain(url($variables['path'], $variables['options'])) . '"' . drupal_attributes($variables['options']['attributes']) . '><span>' . ($variables['options']['html'] ? $variables['text'] : check_plain($variables['text'])) . '</span></a>';
}

and my cumulus block start showing <a href="http://mysite/taxonomy/term/6" style="&quotfontsize:15px&quot;"><span>term-name</span></a>
so i tried to track the problem and i found this on line 202 in cumulus.module
$output .= l($term->name, $uri['path'], array('absolute' => TRUE, 'attributes' => array('style' => '"font-size: ' . $font_size . 'px;"'))) . " \n";

and then I changed my theme_link() fuction to this

function theme_link($variables) {
  if(isset($variables['options']['attributes']['style'])){
    return '<a href="' . check_plain(url($variables['path'], $variables['options'])) . '"' . drupal_attributes($variables['options']['attributes']) . '>' . ($variables['options']['html'] ? $variables['text'] : check_plain($variables['text'])) . '</a>';
  }
  return '<a href="' . check_plain(url($variables['path'], $variables['options'])) . '"' . drupal_attributes($variables['options']['attributes']) . '><span>' . ($variables['options']['html'] ? $variables['text'] : check_plain($variables['text'])) . '</span></a>';
}

Now cumulus block is working fine.

Because of style attribute i was able to solve the problem. but I think there should be some class or id assigned to the link so that it should not break if someone override theme_link().