Pass current language and arguments to portlet

Hello,
i'm starting the development of a portlet and have few questions about 
interaction with jahia:
- how to pass the current navigating language of jahia (without using 
the session to store vars and without putting jahia specific classes in 
the webapp of the portlet)
- hot to pass specific arguments to a same webapp depending on the page 
is called (i.e. in a page i would like the portlet to start with a face, 
and on another page to show the same data but on different way). I would 
like to avoid to instantiate the same portlet multiple time creating 
multiple webapps for each face it may start.

Thank You to anyone may help,
 Lorenzo

-- 
Lorenzo Patocchi
Dipl. Ing. STS/ETS/HTL
lorenzo.patocchi at cryms.com - www.cryms.com
Tel: +41 91 60 55266
Cel: +41 79 375 0891
Fax: +41 91 223 9797

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