Potty Training Trouble

Sophie is almost 3 1/2 years old and has been potty trained for about a year.  She still wears a pull up at night, but not during naps.  However, during the past several weeks she has begun to have accidents.

When I say "accidents" I don't mean one here and there... I mean three to five per day!

Some days she won't have any, but on the days she does, it is VERY frustrating!  She's old enough now and with a big enough vocabulary that when I asked her why she keeps having accidents she gives me many excuses.

"I only had a teeny-tiny accident."  (Said while showing me how big the accident was with her fingers)

"It isn't pee-pee, it's sweat."

"I didn't know and then I just went pee-pee on myself."

"I didn't want Lydia to take my toy.  She always does that when I go away." (BTW-not true!)

"I don't like to go potty.  It's not for me"  (This is my favorite.  Going to the bathroom isn't for you?  Whose it for then?)

I'm sure there are others that aren't springing to mind right now.

When I ask her what I can do to help her remember to go potty.  She said...

"You have to tell me to go."  Ok, so I do and she balks at me!  But, inevitably when I make her sit down on the potty, she goes 90% of the time!

"Maybe you could give me a special prize.  Like candy or something else you know I would like."  I'm really not into giving her "special prizes" for going potty now, when I know she can do it.

So...here's my questions.  Any one else have some regressors?  If so, what tactics did you use to deal with the problem and what worked and didn't work?  Any ideas are most welcome!

Love,
Michelle