MM-YY Format for PostGreSQL

Hey all,

I seem to be having a bit of trouble in formatting a certain type of date.

What I do is this:
Read in a CSV file into a staging table
From the staging table insert it into a production table where everything is formatted and converted properly.

The problem I am having is there is one column in every XLS->CSV that has May-00 in it, of which in the staging table is of type varchar and I can't quite figure out how to convert it to a date for the production table... The production tables dates are formatted as such: 'YYYY-MM-DD'

Any ideas?