Publication date

Hi !

I use Jahia 4.0.6 and I want to use the apache cache server in front-off Jahia for the HTML content. To do that, Jahia need to send some Http Headers to Apache :
- Expires : (now + cache_max_expire_constant) date in rfc822 format
- Last-Modified : last publication date in rfc822 format
- Cache-Control : max-age=cache_max_expire_constant, must-revalidate
- ExpiresAbsolute : (nom + 24 hours) in rfc822 format

My problem is about calculate the "Last-Modified" date : I want to use the date of the publication of the page in the workflow. 

Is it possible with Jahia 4.0.6, because I can't find in Jahia API how to get it ?
Which version of Jahia do I need to use ?

Thanks in advance

Ghislain CUSSONNEAU

DIRR/DPIL/CIS

CAP 44, Rue Marcel Sembat

44000 Nantes

02 51 84 48 80

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