No...you dont need to do that. Im telling you, this will work if you just give it a try.
Step by step
1. Call your cell from an outside line
2. Leave yourself a voicemail
3.Press and hold 1 to access your voicemail from your bb
4.Once your voicmail starts playing, press 7 to delete the voicemail.
5.STAY ON THE PHONE UNTIL PROMPTED TO HANG UP
i called from another line multiple times, ignored them all. went into messages folder, hit alt p to get to phone log. and scrolled up to top as far as you can and then menu delete prior, cleared it up for me. was getting quite annoyed but now its gone. thanks for the tips.