variable expansion not working in $myauthservid definition?

[A. Schulze]

jasonsu:

> 	$mydomain = 'mail01.example.com';
> 	$myauthservid = 'amavisd.${$mydomain}';
use double quotes to allow variable expansion.
single quotes force use as literal string as you see...

-> $myauthservid = "amavisd.${$mydomain}";

Andreas