checkdnsrr, gethostbyaddr / PHP4

hey all! I recently upgraded to PHP4 / Apache 1.3.12 . I have a PHP script that does reverse lookups on IPs. A couple of thouse IPs do _not_ have a reverse entry. For those IPs with reverse entry, gethostbyaddr worked fine. However, for those without reverse entry, PHP prints out a warning saying "Warning: ...could not lookup [bla bla]" I couldnt find a way to turn it off. I then assumed the function would have changed from PHP3 to 4. So I added a line: if(checkdnsrr("xxx.xxx.xxx.xxx","ANY") gethostbyaddr(..... in the hope that this would turn off the warnings... wrong! checkdnsrr doesnt do anything on IPs?!?!? it works for hostnames though?! Am I missing something? Is this a bug? Thanks for any comments or help! -philipp