I have followed the same steps provided in this site (http://hishamgalal.blogspot.com/2009/01/using-file-store-provider-to-store.html) for creating a file store provider to store all the files in database, also created a partition. Still found contents are stored in filesystem. I am using UCM 126.96.36.199.0
In 188.8.131.52, I've noticed yet another quirk with FSP that may be your problem.
Instead of editing the default file store rule for database storage, edit the rule named "DispByContentId", and set it to use database storage.
184.108.40.206 uses this rule "by default" instead of the supposedly "true" default rule. (Yes, this should be filed as a bug.)