Wrong processing _paq.push setCustomVariable

I’m using piwik tracker client code in JSP and piwik server is not on my machine.
But something goes wrong on client code.

On JSP page
_paq.push([‘setCustomVariable’, 1, ‘somevarID’, “text_string/<%= setval%>”, ‘page’]);

On html generated page
_paq.push([‘setCustomVariable’, 1, ‘somevarID’, “text_string/10867/67”, ‘page’]);

In web browser from Firebug Params in cvar I got this

{“1”:"[“somevarID”, “text_string//10867/67”]"}

but actually I need this
{“1”:[“somevarID”, “text_string//10867/67”]}

Why all is processed as single string?
I can’t find what’s wrong?