If you can't use nohup for some reason then you can still "daemonize" your script. Someone mentioned POSIX::setsid() - I have had good luck with using the following subroutine:

sub daemonize {
    my $childpid;
    
    if(($childpid = fork()) < 0) {
    die("can't fork: $!");
    } elsif($childpid > 0) {
    exit(0);        # parent - exits
    }

    (setpgrp() != -1) || die("Can't change process group: $!");
    
    $SIG{HUP} = 'IGNORE';

    if(($childpid = fork()) < 0) {
    die("can't fork: $!");
    } elsif($childpid > 0) {
    exit(0);        # parent - exits
    }
    
    chdir("/");

    umask(0);
}
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This code was borrowed from Stevens' "Unix Network Programming" - a book that should be in every programmers bookshelf...

Michael