10
           
            
                
     
    
    Just to make it more confusing 

 ...
You could also assign the numerical value to a Smarty template variable, and then do the actual display within the template.
footer.php
 $xoopsLogger->stopTime(); 
$xoopsTpl->assign('ftime', $xoopsLogger->dumpTime());  
in template
 Erstellungszeit der Seite = <{$ftime|string_format:"%.3f"}> sekunden.  
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You could also use language strings for the text.
 <{$smarty.const._XXXX}> = <{$ftime|string_format:"%.3f"}> <{$smarty.const._YYYY}>.  
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You might be able to make it work even with caching by using the Smarty 
insert tag.