scoping: can someone explain to me if this should/should not work?

The following code seems to work in general but everyone once in a while I'm getting a segmentation fault. Can someone explain to me why this would be intermittent and/or whether or not it should work? function getDomain($serverName) { $result = $serverName; // some processing to result occurs here echo "here 3: $result<br>"; return $result; } function test() { global $SERVER_NAME; echo "here 1<br>"; $domain = getDomain($SERVER_NAME); echo "here 2<br>"; } When I get a segv, I get the output: here 1 here 3: <appropriate value here> The "here 2" is not displayed. I thought that this would a return by copy and not have an issue. - doug