How to edit my RSS feed

I was checking my RSS feed validation at feedvalidator.org/check, and it found an issue with this line of my RSS feed: <wfw:commentRSS>http://www.thesandinista.com/?feed=rss2&p=11</wfw:commentRSS&gt;

The error message is: wfw:commentRSS should be wfw:commentRss (5 occurrences) It says some users may have problems with my feed if this is not changed – basically making lower case letters of the two S’s.

Is this a change I should make? If so, what is the easiest way to go about doing it.