regular expression help

Simple functions to check & fix if necessary invalid formating of a MAC address... I seem to be having problems with the global variable $mac not being returned from the fix_mac() function. Any help is appreciated. <?php /* * ex. 00:AA:11:BB:22:CC */ function chk_mac( $mac ) { if( eregi( "^[0-9A-Fa-f]{2}\:[0-9A-Fa-f]{2}\:[0-9A-Fa-f]{2}\:[0-9A-Fa-f]{2}\:[0-9A-Fa-f]{2}\:[0-9A-Fa-f]{2}$", $mac ) ) { return 0; } else { return 1; } } /* * check validity of MAC & do replacements if necessary */ function fix_mac( $mac ) { global $mac; /* strip the dash & replace with a colon */ if( eregi( "^[0-9A-Fa-f]{2}\-[0-9A-Fa-f]{2}\-[0-9A-Fa-f]{2}\-[0-9A-Fa-f]{2}\-[0-9A-Fa-f]{2}\-[0-9A-Fa-f]{2}$", $mac ) ) { $mac = preg_replace( "/\-/", ":", $mac ); return $mac; } /* add a colon for every two characters */ if( eregi( "^[0-9A-Fa-f]{12}$", $mac ) ) { /* split up the MAC and assign new var names */ @list( $mac1, $mac2, $mac3, $mac4, $mac5, $mac6 ) = @str_split( $mac, 2 ); /* put it back together with the required colons */ $mac = $mac1 . ":" . $mac2 . ":" . $mac3 . ":" . $mac4 . ":" . $mac5 . ":" . $mac6; return $mac; } } // do our checks to make sure we are using these damn things right $mac1 = "00aa11bb22cc"; $mac2 = "00-aa-11-bb-22-cc"; $mac3 = "00:aa:11:bb:22:cc"; // make sure it is global global $mac; // if mac submitted is invalid check & fix if necessary if( chk_mac( $mac1 ) != 0 ) { $mac = fix_mac( $mac1 ); echo $mac1 . " converted to " . $mac . "<br>"; } if( chk_mac( $mac2 ) != 0 ) { $mac = fix_mac( $mac2 ); echo $mac2 . " converted to " . $mac . "<br>"; } if( chk_mac( $mac3 ) != 0 ) { $mac = fix_mac( $mac3 ); echo $mac3 . " converted to " . $mac . "<br>"; } ?> -- Jason Gerfen "And remember... If the ladies don't find you handsome, they should at least find you handy..." ~The Red Green show