BUG #2643: Auto trim on insert and update

The following bug has been logged online:

Bug reference:      2643
Logged by:          Gene Neely
Email address:      paul.neely@comcast.net
PostgreSQL version: 8.0.x 8.1.x
Operating system:   Linux
Description:        Auto trim on insert and update
Details:

THIS IS NOT A BUG, but a request. Found no place else to submit.
I have found no way to automatically trim fields to the length of the
varchar or char on inserts and updates.
I have tried to create check rules to trim to the varchar length with not
luck.
Can this become a Configuration option???
Doing trims of every variable at every sql command execution takes a lot of
time both coding and lookup the columns length.
Thanks.
Gene Neely