I had thought to buy a Behringer EP4000 power amp but my friend made me a good deal for a XPA-1... it is more money but it is also more beautiful. I do not want problems with the amperage. It worked at 3 ohm (probably less with some frequencies).
Are you sure about there is no problem?
EDIT: Ok, just surfing the web I found it (http://emotivalounge.proboards.com/thread/15571)