[CDBI] Inconsistent reads from database when using web interface

I'm hoping someone can give me some hints on this.  My CDBI application
has a web interface using mod_perl and Mason.  I'm currently using MySQL
with InnoDB. 

The problem I'm running into is that after updating the DB using a web
form, it keeps showing the previous values for a while.  Also, reloading
the page shows the value intermittently, as if some of the Apache
processes were returning a cached result, and some weren't.  This is
very annoying to the user, who thinks that something is definitely
broken in the application.

I thought I had found the problem when I saw this:

http://perl.apache.org/docs/1.0/guide/databases.html#Transactions_Not_Committed_with_MySQL_InnoDB_Tables

However, after following their directions (setting
|transaction-isolation to READ-COMMITTED|, it is still happening.

The question is, what else could be causing this?  Could it be something
in CDBI, and if not, where should I look?

Thanks a lot for your help.

cv