Cookie created with piwik 1.1.1 VS piwik 1.7

Hello,

I use piwik 1.1.1 for a web site in production and I have a pb with cookies.
On the opposite, in my developpment environment I use piwik 1.7.

With the version 1.1.1, one cookie is created.
tc
XXXXXXXXX.XXXX.X.XXX.XXXX
application root/file/
XXX
XXXXXX
XXXXXX
XXXXXX
XXXXXX
*

With the version 1.7, this cookie is created:
_pk_id.1.7XX1
XXXXXXXXX.XXXX.X.XXX.XXXX
application root/
XXX
XXXXXX
XXXXXX
XXXXXX
XXXXXX
*
_pk_ses.1.7XX1
*
application root/
XXX
XXXXXX
XXXXXX
XXXXXX
XXXXXX
*

If I delate it in development environment, it was automatically created again but another cookie is created with it such this one:
tc
XXXXXXXXX.XXXX.X.XXX.XXXX
application root/file/
XXX
XXXXXX
XXXXXX
XXXXXX
XXXXXX
*

In one case, in production, the only cookie was deleted and the application crash.
Can you explain me, why there is a difference between these two cookies?

What is the signification of “tc”?

Is there a parameterization in the file config.ini to generate the second cookie in production like development environment?

Thank you very much for your help.

Regards

Miss

piwik does not create the “tc” cookie, all piwik cookies are prefixed with the _pk