Show day of week in manage posts admin page

I’d like to alter the ‘when’ column in the wp admin -> manage -> posts page to show the day of the week. Currently it shows this sort of info:

2006-11-08 8:00:23 am

I find the minutes & seconds a little redundant; for me day of the week would be way more useful.

Can anyone tell me the lines to hack & what field to put in to reveal the weekday?

Thanks in advance ??

Paul