[LV2] Ardour doesn't find lv2

[rosea.grammostola]

On 12/10/2012 12:18 PM, Harry van Haaren wrote:
> try lv2ls and lv2info:
> lv2ls should list all the plugins on the system
> lv2info should provide all the details of a single plugin given its URI.
>
> Also try using Jalv to load the plugins. If they all work, then the
> issue isn't in the plugin installation, but somewhere else...

Thx for your reply.
Lv2ls doesn't find anything. I've a lot lv2 plugins in  /usr/lib/lv2/ 
though...