Port alias issue on floating rules

[Ryu]

Hello,
recently i'm facing an annoying issue and i don't understand the reason.
i'm receiving very often error messages like this

There were error(s) loading the rules: /tmp/rules.debug:128: macro 'portgroup_web_tcp' not defined - The line in question reads [128]: match  out inet proto tcp  from any to any port $portgroup_web_tcp tracker 1426942399 flags S/SA  queue (qHTTP,qACK)  label "USER_RULE: QueueWeb"

the system create error message for every rule that use port aliases
If i remove the alias in the rule everything goes fine but i don't understand why. consider that these port alias are used on other rules without receiving errors.
Can anyone help me?
thanks