[ic] Quick Entry Sku

[Dan Bergan]

Hello,

I have a "Quick Entry" field where I allow my users to enter a sku from 
our printed catalog and add it to their cart.  If a user enters an 
invalid sku, it just takes them to the basket page with no feedback.  I 
would like to be able to detect when they entered an invalid sku and 
give them some formatting hints.  In the error log I see "Attempt to 
order missing product code", but I'm not sure how to detect that this 
has happened.

I have already added a filter to handle most common formatting problems, 
but I want to take care of the cases when they really mangle the sku.

Can anyone give me some ideas on the best way to do this, or point me in 
the right direction?

Thanks,
Dan Bergan