I'm using 'Flametongue Weapon' and the latter doesn't proc when I use Stormstrike.
I'm not sure if weapon enhancements don't proc for Stormstrike, but the description for the latter does say 'Gives you an extra attack', so it does weapon damage, and it does just that.
It's best if Stormstrike procs weapon enhancements, so I'm not wasting plentiful mana on an extra attack without any procs.
![scared_turtle_head scared_turtle_head](./images/smilies/scared_turtle_head.png)