php to open mail compose window

I thought that a simple php file "email.php" as follows: <?php header("Location:mailto:user@domain.com"); ?> might open a compose window and circumvent those spam robots (the robots that search web pages for email addresses for spam lists). 1) If this worked (a href="./email.php) then WOULD spam robots be circumvented? 2) It does work in NS 4.78. Opera gives an "invalid address" message. IE5.something opens the compose mail window but the web page it was called from goes blank. Thus it is too inconsistent to use. Any way to fix this? Any way to accomplish circumventing spam robots and opening a mail compose window?