BUG #6314: The like command does not handle a long string of special chars

The following bug has been logged on the website:

Bug reference: 6314
Logged by: David Rericha
Email address: d(dot)rericha(at)healthcareoss(dot)com
PostgreSQL version: 8.4.5
Operating system: OpenSuSE 11.4 64-bit
Description:

Simply set a varchar field in your db to the following string:
!"#$%'()*+,-/:;=?(at)[\]^_`{|}~0000&<>

I know, I know, who would do this, right? Well, its for a certification.
The like command works fine up with escapes up to:
!"#$%''()*+,-/:;=?(at)[%
Notice, I added the % to the end. However, if you go any further - no
matches:
!"#$%''()*+,-/:;=?(at)[\\%
Strangely, this works and shouldn't:
!"#$%''()*+,-/:;=?(at)[\%

Thanks.