listening to internet radio realplayer or WMP? mistake!! help!

hi sorry if this is a bit long-winded. i have recently upgraded everything on my powerbook g4 (hard drive ram, the works) it is running great. i like to listen to abc national radio (here in sydney) on my laptop. when i went to listen it asked me to choose which player i wanted to use. realplayer or windows media player. i accidentally pressed WMP and then ticked the box "use this every time" - now it turns out it won't play the radio with WMP. it works with realplayer. this is where it gets tricky. i can listen to the radio station "live" on realplayer but when i go to the show i love and use "listen again" it remembers my "use WMP everytime" command and won't play it!!! it's really frustrating coz i know if i'd hit "realplayer evreytime" everything would be good. can i reverse this somehow? if not i can open safari and use that, but it's just annoying me that i can't do it in firefox which i use all thetime. please help! thanks filo