Campaing Problem

Hello all,
I was just testing the campaigns with two sources: email and twiter.
When I open the email and click the link (web.html?pk_campaign=mail) the campaign get registered in the visit scope. That’s all ok.
The problem came when next to opening the email link I open twitter and click another link with another campaign (web.html?pk_campaign=twitter) then piwik just ignore the new campaign.
I can’t find any solution. I’m using wrong the campaigns?
Thanks for the help

See this one:

I continue the problem in the other thread.