problems with func_get_arg()

Hi, Using the following code snippet function doHead() {

       header("Last-Modified: " . gmdate("D, d M Y H:i:s", getlastmod()) . " GMT");
       if (func_num_args() == 2) {
         doTitle(func_get_arg(0), func_get_arg(1));
       }
       else {
         doTitle(func_get_arg(0));
       }

if I pass 2 argument into the function then I get the following error * Fatal error*: func_get_arg(): Can't be used as a function parameter but passing 1 argument is ok as is using the following code with 2 arguments function doHead() {

       header("Last-Modified: " . gmdate("D, d M Y H:i:s", getlastmod()) . " GMT");
       if (func_num_args() == 2) {
         $a = func_get_arg(0);
         $b = func_get_arg(1);
         doTitle($a, $b);
       }
       else {
         doTitle(func_get_arg(0));
       }

Is there a particualr reason for this or is it a bug? PHP/4.1.2 on Debian Stable (PowerPC) /James -- Technology is a word that describes something that doesn't work yet. Douglas Adams