MacPorts 1.8 beta1: warning messages

[Giorgio Valoti]

Hi,
while building a port, I got these warnings, never seen with with  
previous versions:

> Warning: Skipping upgrade since readline 6.0.000_1 >= readline  
> 6.0.000_1, even though installed variants "" do not match "+darwin".  
> Use 'upgrade --enforce-variants' to switch to the requested variants.
> Warning: Skipping upgrade since openssl 0.9.8k_0 >= openssl  
> 0.9.8k_0, even though installed variants "" do not match "+darwin".  
> Use 'upgrade --enforce-variants' to switch to the requested variants.

Is it expected? Should I reinstall/upgrade ports cited in the warning  
messages?

Thank you in advance
--
Giorgio Valoti