Have a look at http://ez.no/community/news/ez_publish_3_7_0
If your ISP upgraded the php version from the 3.3.x branch to the 3.4.x branch, then you NEED to upgrade to eZ 3.7 See why here http://ez.no/community/articles/reference_issues
I have already seen that documentation. The upgrade document contains information about upgrading to 3.6, not from 3.6 to 3.7: http://ez.no/download/changelogs/ez_publish_3_6/upgrading.