The Oracle 184.108.40.206 patch is the subsequent patch to 220.127.116.11. Because you do not indicate which operating system you are using, it is difficult to determine exactly when 18.104.22.168 was released. For the Windows operating system, 22.214.171.124 was released in July 2005, for Linux it was September 2005, and for Solaris, 126.96.36.199 was available August 2005.
It may be that 188.8.131.52 just became available when the planning started for the migration of databases to Oracle9i. Throughout the planning stages of a migration project, it is not uncommon for another patch to be released. At that point, however, it can be time-consuming to step back and retest for the new patch. In your particular situation, there was a problem discovered during the testing so it makes sense to go to the next release if that rectifies the issue. There will soon be a 184.108.40.206 patch released for Oracle9i -- this is thought to be the terminal release for Oracle9i release 2. At the moment, it is still under development.
This was first published in June 2006