mdunnbass: But, what if i want to be able to match
any 5 out of the 6 characters in string? i.e., the following
would all be desired matches to the pattern ...

This sounds like something from the BLAST
(Basic Local Alignment Search Tool) domain.

There are many pages on this topic, one nice is here.

   The initial search is done for a word of 
   length "W" that scores at least "T" when 
   compared to the query using a given 
   substitution matrix.

Maybe you tell us your problem domain ;-)

Regards
mwa