I just found out that some built in redirects that were in place on the Oracle Blogging platform were removed, and as a result there is a good chance that if you were directed to an entry on this blog that is a bit older you'll get a 404 error.
Luckily there is a simple URL hack that you can use to fix this - switch the "year/month" part for "entry" and then remove the ".html" from the URL.
So for example instead of : https://blogs.oracle.com/shay/2010/10/passing_parameters_to_adf_appl.html
use: https://blogs.oracle.com/shay/entry/passing_parameters_to_adf_appl
I fixed the links on my "Archives" page so you can also look for the entry by title there.
Sorry for any inconvenience.