foreach broken in my script

[Joseph L. Casale]

I  have a list:
@list = ('Exchange','Filter','DNS','Domain');
This is a list of arrays I also have of course to leverage this I am trying to 
. the @ symbol on it during use.

foreach $vm (@list) {
                my_sub("@" . "$vm");
                print "@" . "$vm\n";
}

The print likes this, but the my_sub doesn't? Why not?

Thanks!
jlc